1Why was the question asked? States of Matter Science ... Why was the question asked? 2 What did...

11Why was the question asked?

22 What did students answer?

33 Learnings

44 How do we handle this?

Educational INITIATIVES

Websites:

States of Matter Science: Class 3

Question

Which of the following has air in it?

Class 3 students learn "Air is everywhere; it occupies empty space" We asked this question to check whether children accept air as something that exists and to check if they accept the fact that it is everywhere.

Possible reason for choosing A: It seems children think that air exists only where the effect of air is observable. In this case, the expanded balloon shows the effect of air in it.

Possible reason for choosing B: The possible reason for choosing this option may be that children carry the notion that air

around can fill up an upright cup but it cannot fill up an inverted cup or a closed bottle.

Possible reason for choosing C: It appears that students are possibly guessing while choosing this option. Some of these students might also think

that a closed vessel could contain air but an inverted container cannot.Merely 9% students answered correctly.

! Often when the topic of air is discussed, the balloon is used as an example - therefore they probably connect the two. They do not connect a balloon and air filled in it, in a fundamental way, which is a point

of concern.

! Children think that air is a feeling (sensation) and do not realize that air is also matter. They tend to feel that it is transitory i.e. it comes and goes. For instance, the wind from a fan or wind from trees. Sometimes it exists and sometimes it does not.

! The fact – air is everywhere on the surface of earth – is an abstract concept at this level. “Air”, an invisible thing, being present everywhere might be an idea unacceptable to a child’s mind. Air can not be felt to be present everywhere. Light (in the day time) can be felt everywhere. Children can be made to memorize that air is everywhere but they cannot be made to understand the concept of air by merely mentioning the facts.

Useful resources:

Making Sense of Secondary Science – Support material for teachers by Rosalind Driver, Ann Squires, Peter Rushworth and Valerie Wood- Robinson Routelege Press, London and New York

OptionsOnly 9.1% answered correctlyonly the balloon

the balloon and the open cup

the balloon, the open cup and the closed bottle

all of them have air

A

B

C

D

! Provide more examples of air at different locations like air in the lungs, air in water bubbles, and moving air from the fan, from the trees etc. Flowing air causes papers, clothes or lighter objects to move/fly. This can be used to demonstrate to children the effect air can have. Most importantly, teachers should explain the fact that even when air is stopped and can not be felt, it does exist.

! Force due to air can be a useful tool to teach children about air. An injection syringe can be used, for example. Ask a child to place her finger tightly on the mouth of the syringe, and push the plunger in to force the air out – the child feels the air pressing on her fingertips. Moving a large cardboard swiftly against the air can also make children feel the resistance offered by air. These activities show the presence of air.

! Tell them about outer space where there is no air and where we can not breathe. Show the pictures of earth with spherical layer of atmosphere around and compare with the outer space and the moon. This way possibly children will be able to compare air with no air situation. They will understand that air is another substance that makes the world around us

! Ask other such questions to understand what children’s ideas are. For example – what makes trees move, what makes paper/clothes fly under a fan, why is the fan switched off before brooming a room etc. By questioning their responses further, the teacher should help them form correct and comprehensive ideas about air.

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1. http://www.learnnc.org/lessons/JanWuertz61820024152. http://www.sciencenetlinks.com/lessons.cfm?DocID=156

Books:

68.70%

12.30%

5.20%9.10%

A. 68.7%

C. 5.2%C. 5.2%

D. 9.1%

B. 12.3%B. 12.3% No. of students

10028

P

For any clarifications on this teacher sheet, or to share your feedback, write to us at [email protected], using the feedback format provided to your school. S3-0608-01

a open cup an inverted cup a bottle with a lid an inflated balloon

11 Why was the question asked?


33 Learnings



Scientific Literacy and Scientific Methods Science: Class 3

Question

Which of these is true of domesticated animals?

The ability to recognize important attributes in the process of definition or classification is an important scientific skill. This question tests whether children are able to recognize the key attribute of a “domestic animal”.

44% of students answered Option B correctly, while 36% of students believe that domestic animals can never harm human beings (Option A).

Possible reason for choosing A: Children possibly think that pet animals always behave in the way we want them to, and are always

friendly. It is probably in this sense that children think that pet animals cannot harm human beings in any way.

Possible reason for choosing C: Children are possibly confusing domestic animals with zoo animals.

Possible reason for choosing D: Children are possibly guessing randomly while choosing this option.

Students learn about domestic animals at school and they see different kinds of domestic animals in their daily life. If children understand the main characteristic of domestic animals that separates them from other types of animals, they

should be able to answer this question. The wrong options may appear to be “true” to children because they contain some partial truths about domestic animals. However, children are expected to discern that these are not true all the time, and are less important than the core idea

in Option B. But as the data indicates, clearly, over 50% of students are not clear about this. This indicates not just an issue with the concept of “domestic animals” but possibly with the approach to definition and classification, of other terms, as well. As students progress in learning science, precision in the use of terms, and clarity on attributes driving classification are very important. Children need to understand which generalizations are valid, and which are not. For example, children need to understand that just because most domestic animals are friendly most of the time, doesn’t mean that they cannot harm man. Teachers should encourage critical thinking on these aspects.

Options

Only 44.3% answered correctly

They are friendly with men all the time and can never harm them.

They are useful to man and so he takes care of them.

They are mostly animals from the forest which are kept in zoos.

They are animals who can only eat food cooked by man for them.

A

B

C

D

Definitions should be used to represent the learning in a precise manner and not as a starting point to learn things. Try and introduce the concept first and introduce the definition only after students are clear about the concept. The same holds true for classification in any area.

The goal should be to get students to group organisms based on certain common characteristics. For this particular case, take each option and understand why they are selecting it. And for each wrong idea, try and give an example that challenges their classification. For example, for the option ‘They are friendly with men all the time and can never harm them.’, students might say that they selected it because dogs are friendly to us and do not harm us. Ask them if this will be true even if they beat their dog. Will the dog not bite any other human being? They will themselves think about their ideas critically and develop the necessary understanding once they face such conflicting experiences.

This approach can then be extended to other classifications like the classification of organisms into plants and animals or classification of substances based on physical properties.

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Websites: 1. http://www.trenton.k12.nj.us/Franklin/WebUnits/Grade%203/Grade3ClassicationRev5-11-04.doc2. http://en.allexperts.com/q/Wild-Animals-705/Classification-animals.htm

Useful resources:

C. 13.5%C. 13.5% D. 4

.5%

D. 4

.5%

A. 35.5%

B. 44.3%

No. of students

6581

P




33 Learnings



Living Organisms - Form and Function Science: Class 4

Question

All living things can be grouped as PLANTS or ANIMALS.Which of these in the list below are ANIMALS?

When the classification of living organisms is introduced to children in class 3, they learn that all living organisms fall either in the animal kingdom or in the plant kingdom. This question tests whether children can appreciate that “animal” is a broader category of organisms from a scientific perspective, than what common sense suggests.

Merely 24.3% of students chose the correct answer and 53.8% of students believe that only lion and crocodile are animals.

Possible reason for choosing A: In all probability, students choosing this option have committed a careless mistake of choosing

even grass as an animal.Possible reason for choosing B: In discussions with students we

found that children go by common observation to identify a creature as an animal. They tend to classify organisms based on their external

characteristics that are easily perceivable. The most common response in discussions with students was that an animal is a creature that has four legs and

lives on land. However, “animals” is a far broader category according to scientific classification.

Possible reason for choosing C: Some children are able to appreciate that man is also an animal. However they do not accept fly and fish as animals giving reasons like “an insect is too small and

it can fly” and “a fish lives in water”. It seems that the basic idea of scientific classification is not clear to students who have chosen this option.

It is clear that students are displaying a “layman” approach by giving more importance to externally observable characteristics of animals, and ignoring the deeper scientific aspects they have learnt. This may be happening as scientific distinctions like body structure, body temperature, and mode of reproduction are difficult to observe directly. It is also possible that students at this level find it difficult to categorize one entity into two categories i.e. they may find it hard to understand that an insect can be an “insect” as well as an “animal”.

Useful resources:

Books: Making Sense of Secondary Science Support material for teachers by Rosalind Driver, Ann Squires,Peter Rushworth and Valerie Wood- Robinson Routelege Press, London and New York

Websites: http://www1.phys.uu.nl/esera2003/programme/pdf/232S.pdf

Options


All are animals.

Lion and crocodile are animals.

Lion, man and crocodile are animals.

Lion, man, crocodile, fly and fish are animals.

A

B

C

D

! Biological classification has been developed after an extensive study of organisms all over our planet earth. The basis of this classification is subtle and it is developed in such a way that it accommodates all species of organisms, and covers the vast diversity of life. Help students to appreciate that scientific classification is different and more sophisticated than common perception.

! Organisms are put under one category because they have certain similarities. Sub-categories emerge from that category only because there are finer differences between organisms falling under the same category. There are several organisms that are distinguished from each other based on characteristics like body structure and modes of reproduction. They form separate sub-categories. Ask children to categorize different animals into categories like mammals, reptiles, insects etc. Ask children to reason out their answers and counter others’ ideas. The primary point in this debate should be to recognize the “similarities” at the next higher level of classification in spite of specific “differences” between individual organisms. (e.g. though birds are unlike reptiles, both are vertebrates). One common characteristic of animals is that all of them are organisms that can’t make their own food.

! Use classification trees to help children visualize the previous point. Give children different kinds of exercises in the classification of living organisms.

Fish Fly Man Lion Grass Crocodile

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D. 24.3%

A. 4

.8%

A. 4

.8%

B. 53.8%C. 16.5%C. 16.5%

No. of students

3365

P




33 Learnings



Living Organisms - Form & Function Science: Class 4

QuestionIn which of the following cases will the seeds germinate?

Students learn about how a plant grows - the fact that every plant grows from seeds that they produce, as well as the importance of various conditions like air and water which are required for this. This question was designed to test if students are able to recognise all the factors that help a seed to germinate.

Though around 47% answered D correctly, C was the most common wrong answer, chosen by 36%.

Possible reason for choosing A: Very few students are selecting this option and they are probably just guessing.

Possible reason for choosing B: Students selecting this option are probably just focusing on the fact that water is being sprinkled on the seeds.

But they are ignoring the fact that the seeds are kept inside a refrigerator which will not allow the seeds to grow.

Possible reason for choosing C: Students selecting this option are probably seeing that the sun is present which they know is required for a plant to grow. They might be

relating that fact to this case where seeds are there instead of a plant. But what they seem to be missing is that the cotton is dry and without water, the seeds won’t be able to grow.

There are many concepts like the one being tested - factors affecting seed germination, which are taught to students. Typically these topics are taught in a theoretical manner in the classroom and students do very few experiments on their own on these topics. This makes it difficult for students to internalize these concepts.

The most common wrong answer selected by students indicates that students are probably relating this process of seed germination to photosynthesis. Since both the processes are related to plants and growth, they might be confused between them. And hence while identifying the factors responsible for seed germination, they may choose this option as the sun is predominantly shown here. They do not realize that light is not the only factor that is required for the seeds to grow. Water is also important therefore the answer can only be option D (light is available in this case too as the seed is kept on a window sill).

It is possible that a small fraction of students are making a careless mistake in a hurry by ignoring one of the factors. They might be able to answer the same question if asked in a straightforward way - “Name the factors required for the seeds to germinate.” But in this case, since they have to extract the information from the image, they fail to do so. This indicates the lack of a deeper understanding which could have come by experimenting.

Useful resources:

A good article that describes an open-ended experiment to check germination of radish and factors affecting its germination.

Websites: http://wolfweb.unr.edu/homepage/crowther/ejse/rillero.html

Options


It is important that concepts like these are not just “explained” to students but are figured out by students on their own, with some help from the teacher. Though this is partly an abstract concept, in the sense that students cannot see how water and sunlight makes the seed grow, they can definitely figure out the factors that allow the seeds to grow through simple experiments.

Concepts like these should be taught by allowing students to explore on their own. They can be given seeds and all other required materials. With the basic understanding of conducting an experiment, they should be asked to find out what will help a seed to grow and what will prevent a seed from growing.

Detailed activities are available in the links in the “Useful resources” section.

On wet cotton, placed inside the refrigerator

On dry cotton, placed inside the room

On dry cotton, placed in the sunlight

On wet cotton, placed on the window sill

A

B

C

DP

D. 46.7%

A. 5

.4%

A. 5

.4%

B. 10%B. 10%

C. 36.0%

No. of students

4959P


Why was the question asked?

What did students answer?

33 Learnings

44 How do we handle this


States of Matter

Question

Options

Children are introduced to the concept of evaporation when they are in class 4 in the context of the water-cycle. We asked this question to see if children understand the process of evaporation in a general context and whether they can appreciate the relation between the rate of evaporation and the exposed surface area. Children are expected to answer this question based on a general understanding of evaporation from observations in daily life.

We found that only 40% of students have chosen the correct answer to this question. Nearly 40% of students believe that all three

containers will be left with the same amount of water.

Possible reason for choosing A: Students are probably guessing while choosing this option.

Possible reason for choosing B: Students are probably guessing while choosing this option.

Possible reason for choosing D: Students probably think that since there are equal amounts of water in all three containers, equal amounts will evaporate. Data from

student responses on other questions also point to some other possibilities – Students believe that evaporation takes place only in large water bodies like rivers, lakes and oceans, and

that no evaporation occurs from such containers. Some students believe that water evaporates only when it is boiling at 100 deg. Celsius, and not otherwise.

! It is important for a student of science to develop a spirit of scientific enquiry. This involves an interest in phenomena around us, and an attempt to explain the reasons for these phenomena.

! Given the student responses, it appears that children do not appreciate the concept of rate of evaporation though they have plenty of opportunity to observe this in their daily life. Probably children have not thought about questions like- Why does evaporation occur? Why does water from a container disappear faster at some times? Possibly, they do not make a connection between the “evaporation” they learn in the context of the water cycle, and other contexts of evaporation. Thus evaporation is probably being learned as a “science textbook” thing rather than as a phenomenon seen in daily life. It is important that teachers excite the curiosity of children in the world around them and give them the confidence to make their own attempts to understand the world around them.

! Help children to relate evaporation to the various daily life processes they observe, like the drying of clothes, the drying of water spilt on a table etc. Help them see that drying and evaporation are the same. Expose students to the idea that particles of water escape, during evaporation (though they may not grasp the idea fully at this time). Help them explore when evaporation occurs, and how heat, surface area and other factors affect the rate at which water is lost.

! Teachers need to explain that boiling is a special case of evaporation. During normal evaporation particles escape only from the surface, while during boiling, particles escape from the complete volume of water.

! In summary, it is important for students to appreciate evaporation from a daily life perspective, and help them to build scientific explanations for how the process works.

Useful resources:

Websites: http://www.madison.k12.wi.us/midlinc/carolyn.htm

B

C D

A

Books: Making Sense of Secondary Science – Support material for teachers by Rosalind Driver, Ann Squires, Peter Rushworth and Valerie Wood- Robinson Routelege Press, London and New York

The same amount of water is poured into each of the containers shown below, and they are left uncovered in a warm room. After a day, which container will have the least amount of water left in it?

All will have the same amount of water left.

11

22

Science: Class 5


A. 8.6%A. 8.6%

B. 10.9%B. 10.9%

C. 40.7%

D. 39.1% No. of students 3406

P

P




33 Learnings



Living Organisms – Form and Function Science: Class 5

Question

At which of these times would a plant be making its own food?

Students learn about the basic process of photosynthesis right from class 3. They learn about the raw materials required by plants to make food as well as conditions under which they can make food. This question was designed to test this very basic understanding of one of the conditions - sunlight, required by plants to make their food.

Though around 44% of students answered A correctly, D was the most common wrong answer, chosen by around 35%.

Possible reason for choosing B: Students selecting this option are probably just looking at AM. They might be thinking that AM

means morning and PM means night. And while selecting between options A and B, they might be choosing B thinking that the intensity of

sunlight is more in the afternoon.

Possible reason for choosing C: Students selecting this option seem to have not understood the question and are most probably guessing.

Possible reason for choosing D: Students selecting this option are probably confused between the two processes - photosynthesis and plant respiration. They

probably think that the two processes are inseparable. They think that to maintain a balance between the gases in the atmosphere, plants take in carbon dioxide all the time, as opposed to

animals who take in oxygen all the time. And since they know that carbon dioxide is used in the process of photosynthesis, they probably extend this to conclude that plants make their food throughout the day and

the night, ignoring the fact that sunlight is also required for photosynthesis to take place.

Student responses to this and other questions related to photosynthesis and respiration indicate that students do not have a clear idea about these processes and the linkages between them. For example-• Photosynthesis may be thought of as “respiration” in plants• That respiration requires oxygen and is a process that releases energy from the consumed “food” is not clear

Based on student interviews, a study of textbooks and teacher interviews, we believe that students are taught about these important processes through “definitions” and in a piecemeal way. Several valid questions that arise in children’s minds about these processes are not brought forth and addressed. As a result of this, children try to put the missing pieces together and end up with many misconceptions.

Useful resources:

Websites: http://biology.arizona.edu/sciconn/lessons2/Roxane/photo.htmThe section on 'Plants, Photosynthesis and Respiration' at this link talks about a simple experiment that can be used to demonstrate that plants also respire.

Options


9 am

3 am

8 pm

At all times of the day and night.

A

B

C

D

Students should understand the two life processes – photosynthesis and respiration. But it is important that they understand them in context of living organisms. Photosynthesis is specific to plants. But when it comes to respiration, it is common to all living organisms. Therefore while teaching, it is important that respiration is not taught just in the context of animals.

Instead of teaching the definition of processes like photosynthesis and respiration, it is much more important to teach the underlying concept and the role of these processes in sustaining life. And therefore it would help if definitions are given only after students have internalized these concepts. In fact students could be encouraged to come up with their own definitions, after grasping the concepts.

Allow students to experiment with different plants to find out the factors affecting photosynthesis. Simple experiments can be designed to make them see the role of sunlight or water in the process of photosynthesis. A similar one can be designed to explain the process of respiration.

P

P

C. 6.9

%C.

6.9%

D. 35.3%A. 43.5%

B. 13.6%B. 13.6%

No. of students

1124




33 Learnings



Energy, Energy Transfer & Energy Conversion Science: Class 6

Question

Blankets made of wool protect us effectively fromcold because _______________________

In class 6, children learn about energy, heat transfer and conductivity. They are taught that all materials can be classified on the basis of their thermal conductivity. They are also taught how different kinds of clothing suit us in different weather conditions. This question was asked to check whether children understand how woolen clothes keep us warm.

Only 35.3% of students answered B correctly, and 37.5% of children believe that wool keeps us warm by generating heat.

Possible reason for choosing A: Students have observed fires and other hot objects giving out heat and warmth. When they wear woolen

clothes they feel a similar warmth. This probably leads them to think that wool generates heat. The fact is that wool is not a heat source.

Possible reason for choosing C: Possibly children think wool stops the movement of the “cold outside air” through the blanket and keeps us warm.

Although air transfer is poor in wool, it is not the primary reason for wool to keep us warm.

Possible reason for choosing D: Students selecting this option possibly think that some heat is coming to the body from outside and that heat is not able to go out of the woolen fabric. They

possibly do not recognize that the heat is generated by the human body itself.

! It seems that students are stuck with the unscientific idea of “whatever keeps us warm generates heat”. In reality it is the human body that generates the heat and the woolen clothing prevents the heat from going out. The structure of the wool is such that it traps the air inside it between its layers. Air being a bad conductor of heat, does not conduct the heat towards the outer layers of the woolen clothing.

! A related difficulty some students seem to face is to think that wool prevents coldness from flowing into our body. They tend to think that if the outside atmosphere (or material in contact) is hot, then heat will be transferred to our body and if the outside atmosphere (or material in contact) is cold then coldness will be transferred to our body. Logically this may be correct but according to the convention in science there is no such thing as coldness. of the notion of coldness is faulty-it is only heat which flows, from a higher temperature to a lower temperature.

Useful resources:

Books: Making Sense of Secondary Science – Support material for teachersby Rosalind Driver, Ann Squires, Peter Rushworth and Valerie Wood- Robinson Routelege Press, London and New York

Options


wool is a hot material which generates heat and keep us warm.

the air trapped by the wool prevents body heat from leaving.

the air in the wool prevents the cold air outside from reaching us.

wool allows heat to enter through it but not to leave it.

A

B

C

D

Key things to understand How to do it?

Wool does not generate heat,it simply prevents heat transfer.

! Take two thermometers. Keep one in wool and one in the open. Show the students that the readings in both the thermometers are the same and thus wool does not generate heat.! Put some ice in wool and some ice in the open and demonstrate to children that the ice in the wool takes longer to melt.

Air is a bad conductor of heat. ! Light a flame and tell children that the temperature of the outside zones of flame is 1800 deg C. We still do not get burnt even near the flame because air is a bad conductor of heat.

Connecting the pieces together-It’s not wool, but the trappedair in the wool!

! Compare the heat flow prevention in the outward direction by wool on the human body and the heat flow prevention in the inward direction on ice. Help children to understand that the air trapped in the wool inhibits the transfer of heat.

Websites: http://www.exploratorium.edu/ifi/resources/workshops/teachingforconcept.html

P

P

C. 12.0%C. 12.0%

D. 14.7%D. 14.7%

A. 37.5%

B. 35.3%

No. of students

5073

No. of students

5073



What did students answer?

33 Learnings



Living Organisms – Form and Function

Question

Students learn about body movements in class 5 and class 6. They are taught about the skeletal system, various types of joints and the mechanism of their movements at these levels. This question was designed to test if students can identify the hip joint in the skeleton correctly.

Just above half the students answered this question correctly. 37.4% students answered option C.

Possible reason for choosing A: Students selecting this option are most probably guessing.

Possible reason for choosing C: Students selecting this option are probably confused between hips and buttocks. They might be thinking that

hips are on the back side of the body and hence are selecting option C.

Possible reason for choosing D: Students selecting this option are most probably guessing.

! The question expects students to locate the position of hip in the human body and find out the hip joint based on that. However, the most common wrong answer given by students indicates that students are not clear about what hips are and are probably confusing it with buttocks. They don't seem to understand that hips are located on the sides, below the waist and above the thighs where as buttocks are located on the back side, below the waist and above the thighs. And this confusion might be making them think that the hip bone is in the buttocks, on the back side.

! Students learn about various kinds of joints in the body like ball and socket joint, hinged joints etc. with examples. They study that the hip joint is a ball and socket type of joint. But they don't seem to be relating that understanding with the structure in this case. If the understanding were to be there, they could have felt the type of joint in the body and answered the question. But it seems to be missing and they seem to be learning such things like the structure and function in isolation to each other.

! The general types of joint in the human body are ball and socket joint, pivotal joint, hinge joint and fixed joints. Let students understand not just the type of joints but even their functions by making students move the various bones in their body. For example, ask them to move their legs and check in what all directions they can move it. And then related it to the types of joints they have studied. Classifying this way will help them retain the understanding.

! Use resources that can help demonstrate such topics in an animated fashion. (For more information check internet links in the 'Useful resources').

Useful resources:

Websites: • http://library.thinkquest.org/5777/ske7.htm• http://www.saburchill.com/chapters/chap0008.html#Link

The figure of the human skeleton is given.

Which arrow points to the hip joint?

11

22

Science: Class 6


BC

D

A

•• http://www.sickkids.ca/childphysiology/cpwp/Skeleton/SkeletonAnatomy.htm

http://www.bbc.co.uk/science/humanbody/body/factfiles/joints/ball_and_socket_joint.shtml

P

P

A. 2.4%

B. 53.7%

D. 5

.7%

D. 5

.7%

No. of students 3406C. 37.4%




33 Learnings



States of Matter Science: Class 7

Question

What is the chemical formula for steam?

Chemical names remain the same when substances change their physical form. When water turns into steam it is a physical change. Water and steam are chemically the same substance. This question was asked to check whether children appreciate that steam and water are chemically the same thing.

Only 15.6% students have answered the question correctly whereas 68.9% students have answered that steam is a mixture

and does not have a chemical formula.

Possible reason for choosing A: Very few students have chosen this option and this appears to be mainly random guesswork.

Possible reason for choosing C: Very few students have chosen this option and this appears to be mainly random guesswork.

Possible reason for choosing D: From discussions with students, we come to know that many students believe that water breaks down at a molecular level

when it changes to steam. The possible reason why they think in this manner is that they cannot imagine water itself in a gaseous state. It is also possible that children are not

fully clear that “steam” is the same as “water vapour”.

Useful resources:

Websites: http://www.quia.com/quiz/303980.htmlhttp://www.chem4kids.com/files/matter_states.html

Options


CO

H O2

O2

It is a mixture, so it does not have a chemical formula.

A

B

C

D

! Break a wooden stick, or bend a soft piece of aluminum in class (see other examples to use in Useful Resources: 1) and ask students - what kind of a change is this – physical or chemical? Ask them to explain why and challenge their ideas on this. After this, tell them that a physical change is defined as a change in which the chemical structure is not altered.

! Help with Visualization- Use thermocole balls of different colours and proper relative sizes to demonstrate chemical changes and physical changes. Show the formation of water by sticking balls of hydrogen and oxygen. Make many such water molecule models and show the physical change of evaporation by spreading them apart and show condensation by bringing them closer. After this explain how evaporation, condensation, melting, and boiling are also physical changes.

! Tell students that the chemical name of a substance remains the same even when its physical state or physical form is changed. For instance, if water is condensed to ice, its physical form changes to solid and its common name changes to ice but its chemical name remains “H O”. Similarly diamond and graphite are two different physical forms of carbon and thus though physically they are quite different, 2

their chemical name remains “C”.

P

! ASSET responses and student interviews reveal that students think that boiling breaks down the water molecule. Many students believe that water breaks down into atoms of hydrogen and oxygen. Some believe that hydrogen gas and oxygen gas (H and O ) are formed. Most probably they are seeing this combination of gases as a mixture and are therefore answering D. It is important for them to 2 2

know that water remains as H O even after boiling.2

! Another point to note is that “H O” is the “chemical name” for the substance “water” and if this substance changes its physical form from being a liquid to being a gas, its chemical name does not change. 2

Clearly, students do not appreciate the fact that here only the physical form of water is changing and this will not alter its chemical name or chemical formula.

C. 8.3%C. 8.3%D. 68.9%

B. 15.6%

A. 6

.7%

A. 6

.7%

No. of students

1124

P

Books: Making Sense of Secondary Science – Support material for teachers by Rosalind Driver, Ann Squires,Peter Rushworth and Valerie Wood- Robinson Routelege Press, London and New York




33 Learnings



Electricity and Magnetism Science: Class 7

Question

Which of these options correctly shows the north andsouth poles of a horseshoe magnet?

Most children have played with magnets from the age of 5 or 6 years. In class 6, they are introduced to magnetism formally, and taught about different types of magnets and magnetic poles. Significantly, they are taught that every magnet has opposite poles and that the poles of a magnet cannot be “separated” by breaking the magnet. This question tests whether children are able to apply this knowledge to identify the poles of a horseshoe magnet, as opposed to a bar magnet with which they are more familiar.

Around 32% of students answered C correctly, while an equal number of students answered D- “Horseshoe magnets do not have North and South

poles unlike bar magnets”.Possible reason for choosing A: Students are possibly influenced by

pictures of bar magnets where one half is shaded black and the other white. Not knowing where the poles of a horseshoe magnet are, they are possibly treating

each “leg” of the horseshoe magnet as a bar magnet with one “black” pole and one “white” pole.

Possible reason for choosing B: Only a few students have chosen this option and have probably guessed randomly. General practice says that opposite poles are on opposite sides.

Students might have confused opposite sides to be opposite faces and have chosen this answer.Possible reason for choosing D: Possibly, students are unable to accept the positions of North and South

poles given in Options A, B and C (A and B because the poles are not at “ends” and C because both the poles are on the “same side”). Given this, they have decided that “Horseshoe magnets do not have North and South poles!” – A

conclusion that violates the basics of magnetism.

Students seem to be influenced more by superficial patterns they have observed about magnets, and have not grasped the deeper concepts underlying magnetism. They pay more importance to poles being on the opposite side, or the magnet being shaded in different colours in drawings, while imagining that some magnets need not have North or South poles! This may be partly due to the way the curriculum presents magnets. Typically, a lot of facts are presented with little explanation of how magnets actually work. With a proper understanding, students should be able to figure out that a horseshoe magnet is nothing but a bar magnet bent into a “U”, and thus be able to identify the poles correctly. However, many students might have just recalled drawings of the poles of horseshoe magnets.

Useful resources:

Options


A B

C DN S

N S

N

S

Horseshoe magnets do nothave North and South Poles

unlike bar magnets

! Magnetic field lines can help students visualize the poles of a magnet- we recommend introducing some basics of magnetic field lines at this level. These lines always originate from the North pole and end in the South pole. All magnets have these lines just as all magnets have the two poles. Draw the field lines for a bar magnet, a horseshoe magnet and magnets of other geometries on the board.

! Using the field lines more concepts can be taught – attraction between opposite poles and repulsion between similar poles. (See useful resources: 3)

! Give children different types of magnets and iron pins to play with. Encourage them to get a feel of the field lines and force operating at different poles, by doing simple experiments.

! Ask and discuss thought provoking questions in class that help to deepen the understanding of magnetism. Questions like-How can one make a horseshoe magnet? Can you make one by bending a bar magnet?

22.00%

12.20%

32.40%

32.50%C. 32.4%

D. 32.5%

A. 22.0%A. 22.0%

B. 12.2%B. 12.2%

No. of students

3817

P

P


Websites: http://www.standards.dfes.gov.uk/schemes2/secondary_science/sci08j/?view=get http://micro.magnet.fsu.edu/electromag/java/magneticlines2/ http://www.school-for-champions.com/science/magnetism.htm



33 Learnings



States of Matter

QuestionWhen water is boiled in a closed container it turns into steam. In Figure P, Vinay has drawn a magnified view of a small portion of liquid water in a closed container. Which of the following would BEST represent the magnified view of the same part after water turns into steam?

Students are introduced to the concept of evaporation of water in class 4 when they study the water cycle. In class 7, they learn that everything around them is made of atoms and molecules. At this level, they also study about the properties of various substances and the physical and chemical changes involving these substances. We asked this question to students to gauge if they understand these concepts in their entirety and whether they can connect these different ideas.

More than 50% of the total students answered this question incorrectly.

Possible reason for choosing A: Students seem to believe that heat separates the water molecules into its constituents.

Possible reason for choosing C: Some students have the “information” that hydrogen and oxygen cannot exist in their atomic states.

Thus, after decomposing water into hydrogen and oxygen atoms, they form hydrogen and oxygen gases as H and O .2 2

Possible reason for choosing D: Children who chose this option are most probably guessing. After decomposing water into hydrogen and oxygen atoms, they

form another combination of hydrogen and oxygen atoms.

Chemical changes and physical changes involve molecular transformations. It is only in terms of the molecular model that we can associate definite rules for these changes. A chemical change is a regrouping or a separation of atoms in molecules, while a physical change is

only a rearrangement of the molecules of a substance. Children do not seem to be clear about the kinds of changes and how these are different from one another. They are unable to connect different concepts they have learnt like the atomic/molecular model of matter, physical/chemical changes and evaporation of water.

Useful resources:

Websites:

Options

Books: Making Sense of Secondary Science Support material for teachers by Rosalind Driver, Ann Squires,Peter Rushworth and Valerie Wood- Robinson Routelege Press, London and New York

11


A B C D

Figure P

Key things to understand How to do this?The particle model is realand not merely a representation.

! The atomic sizes pose a challenge in understanding the “reality” of these particles. Go back to the basics if required- get children to recall that they must have seen dust particles in the air. Tell them that there are 100,000 atoms in every dust particle. (See Useful Resources for more such activities)

There are changes happening all around us. Almost all of them can be categorized into a physical change or a chemical change.

! Break a wooden stick, bend a soft piece of metal like aluminum in class and tell students that these are physical changes. Mention evaporation, condensation, melting, boiling as physical changes too and tell the students that as the molecular structure does not change in all these processes we call them physical changes.

! Conduct small experiments in class to expose children to different kinds of chemical changes. Tell students that as the molecular structure changes in these processes we call them chemical changes.! Help with Visualization- Use thermocole balls of different colours and proper relative sizes to demonstrate chemical changes and physical changes. Show the formation of water by sticking balls of hydrogen and oxygen. Make many

such water molecule models and show the physical change of evaporation by spreading them apart and show condensation by bringing them closer.

Understanding the particle model is central to understanding all the three concepts – atomic/molecular model of matter, physical/chemical changes and evaporation of water.

The understanding can be deepened further by allowing discussions among students and between students and teachers, attempting to build models of what we see around us and experience.

http://www.chem4kids.com/files/matter_states.htmlhttp://www.sciencenetlinks.com/lessons.cfm?Grade=6-8&BenchmarkID=4&DocID=160

P

: Science Class 8

C. 9.4%C. 9.4% D. 6

.4%

D. 6

.4%

A. 34.4%

B. 48.5%

No. of students

3968

P




33 Learnings



Living Organisms – Form & Function : Science Class 8

Question

Children learn about the basic life processes from grade 3. But they often see certain processes as specific to certain organisms, like photosynthesis as specific to plants or respiration as specific to animals. This question was asked to check if students really understood the difference between the two processes of photosynthesis and respiration. This was tested across classes 5 to 9, to see if there is any difference in performance.

Only about 19% of class 8 students selected the correct answer (A). We asked this question to students of classes 5 to 9. The most surprising fact is

that the performance is almost the same across the classes. In fact, the percentage of students selecting the most common answer (C)

increases with the class.Possible reason for choosing B: Very few students have selected B and are

most probably guessing.Possible reason for choosing C: These students are perhaps confused between

respiration and photosynthesis and consider any gas exchange process taking place in plants as respiration.

Possible reason for choosing D: They might be considering respiration as a process in which energy is released and so consider even combustion as an example of respiration.

Confusion between ‘Photosynthesis’ and ‘Respiration’: Students seem to be confused between the two processes – photosynthesis and

respiration. They might have a notion that respiration is a process in which gas exchange takes place. And this could be the reason they think the process whereby plants use carbon dioxide and release oxygen can also be referred to as respiration.

Some students who give the correct answer (A) show an incorrect understanding when probed. According to them plants perform photosynthesis during the day and respire during the night. Some students think that since the Sun is required to carry out photosynthesis and there is no Sun during the night, they switch on to respiration as it is also important for them to produce energy. There are others who think that plants can use only one gas at a time i.e. when the plants are using carbon dioxide they cannot simultaneously use oxygen and so in the day they carry out photosynthesis and at night, respiration.

But whether they know that respiration is required for producing energy or not, the fact that both, respiration and photosynthesis, occur simultaneously in plants is just not clear. Students could even be thinking that it is not necessary for organisms to respire continuously. This should be probed further.

Useful resources:

Websites: http://www.bbc.co.uk/schools/gcsebitesize/biology/greenplantsasorganisms/0photosynthesisrev6.shtmlA very good link that shows both the processes occurring simultaneously in plants during the day.

Options


only 1

only 2

only 1 and 2

1, 2 and 3

A

B

C

D

! Students need to understand that both these processes can occur simultaneously.! Let them understand the process of respiration without any organism's context. So, just teach the process independent of animals or plants. Just make them clear about why the process is important and

what happens in the process. Then lead them to which all organisms will need to respire. And from there lead them to the time at which respiration occurs.! Many students have a misconception that plants or animals take in only one gas, carbon dioxide or oxygen at a time. It is important to correct this and teach that it's the mixture of gases that is taken in out

of which the important gas is utilized (by filtering through lungs in case of animals and diffusion in case of plants).

C. 54.6%

D. 21.9%D. 21.9% A. 19.4%

B. 3.9%B. 3.9%No. of students

8440

P

Which of the following are examples of respiration?

1. Humans use oxygen and release carbon dioxide. 2. Plants use carbon dioxide and release oxygen. 3. Burning dry leaves uses oxygen and releases carbon dioxide.

O2 CO2O2O2CO2CO2

Day Night

Students think that- only one of the processes occurs at a time OR- only one gas can enter at a time

http://biology.arizona.edu/sciconn/lessons2/Roxane/photo.htmThis page has a set of experiments to help children explore different aspects related to respiration and photosynthesis in plants and understand them in greater detail.

P


Properties of MatterASSETASSETTM


Why was the question asked?By class 9, students learn about different properties of various materials and how these are used for different purposes. In this question, the process of extraction of sulphur is described and students are asked that what properties of sulphur make this process possible. This question is important from two perspectives: Students should be able to identify the useful information from the mass of information provided in the question. Secondly, they should be able to appreciate that complicated industrial processes are based on specific properties of substances involved. P.T.O.

Science: Class 9

Question


P Its atomic mass is 32

Q It has 16 neutrons in an atomoR Its melting point is 112.8 CoS Its boiling point is 444.6 C

T It is insoluble in water

W It combines with oxygen

Frasch Process

Above ground

Below ground

Hot waterCompressed air

Liquid sulphurConcentric pipes

Compressed airLiquidsulphur,air, water

Sulphur

Super-heatedwater

0 (above 100 C)

Since sulphur in the free state is found at depths of more than 150 meters below the earth's surface, the method of extraction of sulphur differs from other materials. The figure given below depicts this. In this process, super-heated water and compressed air are passed underground through pipes. Due to the pressure, liquid sulphur flows out of the pipe.

Options

A P and Q B R and T

C S and W D Q, S and W

P

1

A. 8.0%A. 8.0%

B. 50.2%

C. 26.2%

D. 14.5%D. 14.5%

No. of students

2375

P



Useful resources:

S9-0608-01

Possible reason for choosing A: Very few students have chosen this option indicating that they are just guessing.

Possible reason for choosing C: Students are probably focusing on the information that there are drastic conditions for sulphur – like super-heated water and compressed air – which may have led them to think that there is a chemical reaction taking place. Because of this, they may have concluded that sulphur combines with oxygen, and chosen C. Another possible reason for choosing this option could be mix-up between boiling point and melting point.

Possible reason for choosing D: While many of these students are probably guessing, it is possible that they believe there is a chemical reaction happening here for the reasons stated in the previous paragraph.

! It appears that children have difficulty in extracting the relevant information from the details provided and are not able to comprehend the question properly. They are going to come across many such processes in higher classes, and it is an important skill to collect relevant information from a mass of information provided. For example, sulphur is actually coming out from beneath the surface, through the tubes, in liquid state, as the question specifies. This is the information to be used and not that hot compressed air being sent under the ground.

! The process of extraction of elements and minerals are always based on some property of the substance to be extracted. These properties if ignored make the whole process of extraction pointless. There remains no clue of why and how things happen in the process. The scientific approach gets lost and the entire process becomes rote. As it becomes rote it becomes heavy both to teach and to learn. On the other hand if the process is taught and learned based on principles like properties of material involved, not only the subject will become more scientific it will also become easier to handle.


3 Learnings

4 How do we handle this?Key points for understanding

! Making children think analytically i.e. seeing what information is relevant to the question and what information is irrelevant.

! To make children more aware about the significance of material properties in various practical applications.

How to do this?

! Help children to understand such problems in a systematic way, by asking them to jot down things like- What is the question asking? What information in the question/ drawing might be useful to answer the question? What information is probably not useful? You could even ask groups of children to discuss their views on these questions.

! Use examples such as copper. Let students discover how it is used in power transmission cables because of high conductivity, good ductility and abundance. Another possible example is gases used in tyres of vehicles and not liquids, because of their high compressibility. Ask students what other materials could be used as substitutes. This will make students focus on the properties of material important to the process/ application rather than just learning the use by rote.

Making Sense of Secondary Science – Support material for teachers by Rosalind Driver, Ann Squires, Peter Rushworth and Valerie Wood- Robinson Routelege Press, London and New York

Books:



33 Learnings



Human body Science: Class 9

Question

Students learn about the structure of the heart and its various parts – atriums, ventricles and also about its functioning in the context of the circulatory system. This question was designed to test if students are able to interpret the given visual and apply their understanding of the structure of the heart to locate the position of left ventricle in it.

About 42% of the students selected the correct answer. However, 36% of the students selected the wrong answer B.

Possible reason for choosing B: Students are probably just catching the word 'left' in the question and selecting B thinking that the

ventricle will be below the atrium and on the left side in the diagram.

Possible reason for choosing C: Students selecting this option might be thinking that the ventricle is to the left of the atrium. They might be seeing

the right atrium marked in the figure and so might have selected C thinking that it will be the left ventricle.

Possible reason for choosing D: Students selecting this option have not understood the question and are most probably guessing.

Students learn about the structure of heart and its various parts. They learn about various terms related to the heart like atrium, ventricles, pulmonary artery, pulmonary vein etc.

Given this, they are expected to correctly point out the left ventricle in the given diagram. They should understand that the ventricles are below the atriums in the heart and since we have shown the right atrium, the chamber on its left would be the left atrium and below it would be the left ventricle.

But it seems that students are not able to identify it correctly. This is a common error that they make. Typically the structure of heart is shown as a front view and so the actual right side of the heart is seen to us as the left, and this sometimes confuses students. However, to make sure that students do not make that error, the right atrium was marked in the figure. But perhaps they haven’t understood the structure of heart – atriums which receive blood from the organs and are hence are on top and ventricles which pump blood to the organs and are hence below the atriums. This could be because of the way such topics are taught – the structure and function being taught independently.

Useful resources:

Websites:


! Use a plastic model of the heart to teach the structure.

! Without actually showing the structure first, try and teach it in relation to the function of each separate organ and just allow students to visualise the structure and represent the same as a diagram. For example, they can know what the atriums, ventricles, various arteries do and then draw the structure of the heart as they would see the function of each falling in place. An exercise like this can help them actually link the function to the structure. Support it using the diagram after they have internalized the structure-function of the organ.

! Use resources that can allow the students to take a virtual tour of the heart, manipulate and check the various organs and their functions. It will help because as far as organs like these are concerned, they do not really get an opportunity to physically explore them. (For more details check the ‘Useful Resources’ section.)

Study the picture of the human heart.Some parts are marked on it.

Which letter represents the left ventricle?

http://www.medtropolis.com/VBody.aspA good website that teaches the structure of heart and its functions by virtual representation of the same.

http://www.fi.edu/learn/heart/index.htmlA good resource talking about the structure and function of the heart.

C. 12.8%C. 12.8%

D. 8.4%D. 8.4%

A. 41.8%

B. 36.3%

No. of students

2729

Coronary ArteryCoronary Artery

PulmonaryVeinPulmonaryVein

Right AtriumRight Atrium

A

B

C

D

P

P


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