Curriculum and Instruction

Pendulum Activity Lillian Meyer

Essential Concepts & Skills:Iowa Core/Next Generation Science Standards, Grades 3-5. Disciplinary Core Ideas:

3-5-ETS1-3. Plan and carry out fair tests in which variables are controlled and failure points are considered to identify aspects of a model or prototype that can be improved.

3-PS2 Motion and Forces: Make observations and/or measurements of an object’s motion to provide evidence that a pattern can be used to predict future motion.

Science & Engineering Practices:

● Analyzing and interpreting data

● Obtaining, evaluating, and communicating information

● Planning and carrying out investigations

21st Century Skills: ● Communicate & work productively with others ● Adjust to various roles & responsibilities ● Practice leadership skills

What students will be doing: In this activity, students have a chance to practice the skills

they have learned related to setting up a fair test. In doing so they will also demonstrate their understanding of all of the science terminology associated with a fair test.

Materials: ● Trays for each group, each tray needs

○ Pencil ○ Tape ○ String ○ Paperclip ○ 4 washers ○ Scissors ○ Envelope with cards for the Fair Test card sort activity

Activity Setup and Organization: Cut out the cards for the Fair Test card sort and place them in envelopes, one envelope for each group. Collect all the supplies for the activity and put them on trays, and put a tray out for each group of students.

Introducing the Activity Concept Map Greet the class, then say “Today we will be doing an activity to work on our ability to do a fair

test. So, since we’ve already learned about fair tests, I have a bit of a review for you all to do. Look on your trays on the table, you should all have an envelope with cards in it. As a group, I would like you to match the cards, and organize them in a way that has meaning to you.” Walk around the room, supervising the students, making comments on their matching and organizing. “When you’re done with matching, go ahead and start writing down the vocabulary words on your thinking log when your group is done.” Give the class time to write down their concept map.

Pendulum Introduction “Alright, looks like most of us are done. Our experiment today focuses on Pendulums. Has

anybody heard that word before? Who has examples of a pendulum?” Take student responses to the two questions, perhaps a wrecking ball, grandfather clock, etc.. “What about a swing? Do you think a swing is a pendulum?” Ask some questions about swings, for example;

● Does a swing swing differently when there is a big person on it versus a little person? ● How do you make a swing go faster? ● How do you make a swing go slower?

“Well, today we are going to be making our own pendulums. On your trays, you’ll see a pencil, a string, a paperclip, some washers, and some tape.” While you are saying the directions, model the actions. “We’re going to tie the paperclip to one end of the string, and the pencil to the other end of the string. Then we can tape it to make sure it won’t wiggle loose. Then we can put as many washers as we want on the paperclip. We will also attach the pencil to the table, to keep it from wiggling. Now look!” Describing the swing/how you count a swing Make the pendulum you have made swing. “We’ve made a swing! Or, a pendulum. What kind of motion do you think this has?” Take a student’s response. “Swinging,” or “back-and-forth,” is what we’re aiming for. “So, in our experiments, we will need to count the number of swings in fifteen seconds. Here, we’ll practice. I’ll swing mine, and you all count. Ready? Go!” Let your pendulum swing while you count 15 seconds, then stop the pendulum. “How many swings did you count?” Students will likely have two different answers, a big number and a small number. “Why do we have two different numbers?” Student answer, something like “some counted when it changed directions, and some counted when it went back to start.” “Yes, so we will want to count the smaller number, when it gets back to the starting side, the full back-and-forth motion. There’s a spot for you to write that on the bottom of your thinking log, go ahead and do that now.” Displacement “Our first experiment is measuring displacement. Displacement is how far the pendulum is drawn back. So this” pull the bob back a little bit, “is a little displacement. This” pull the bob back a lot, “is a big displacement. You all will need to figure out a way to measure that in your groups. There is one more thing on that first page we need to discuss. Who knows what the mass is in

this experiment?” Student response - “the washers” “Yes, the washers are the mass. How will we measure how much mass is on the pendulum?” students - “the number of washers” or “the weight of the washers” “As we don’t have a scale on our tables, weighing doesn’t seem possible right now. The number of washers seems like a good way to measure that. Go ahead and fill out that first page of your thinking log. Make sure to draw the pictures!” Give the students time to work on that. Predictions “Alright, one last thing to do before we start experimenting. We need to make predictions. In some experiments we don’t do this, but we’ll do it today. I would like everybody to write down their predictions in their thinking log. All three pages have a prediction. I would like you to think about them, write them, and then don’t touch them. It’s alright if it turns out wrong. I just want to see that your brain was thinking about it.” Read the research questions out loud,

● “What is the effect of displacement on the number of swings in 15 seconds?” ● “What is the effect of mass on the number of swings in 15 seconds?” ● “What is the effect of length of the string on the number of swings in 15 seconds?”

Give the students time to write, circling the room. Experimenting “Alright, now that you have finished your predictions, we’ll take a quick look at the thinking log. Make sure you write the independent variable, and the dependent variable in the spaces at the top of the page. Also make sure to fill in all the slots on your table. Go ahead and get started, I’ll be circling the room if you have questions.” Circle the room, answering questions. If students’ pencils start wobbling, make sure to point it out, and have them try again. When they start finishing the first experiment, say “Make sure you write your claim before you move on to the next page!” If they struggle with the empty table, tell them that it’s important that they figure it out for themselves, and they were just working on a table they can refer to. Summary At the end of the experimenting, have a group discussion about the experiment. “How many of you had accurate predictions all the time? Who got at least two of them wrong? This is an important part of science. Sometimes, what you predict is not what actually happens. That’s okay! What matters is that you thought about what you know, and made a guess. The experiment will tell you whether your guess was right. That’s why nobody is graded on the accuracy of the prediction, only on whether it’s there. Because it’s important to be thinking about what’s happening.”   

 

   

 

Example of Completed Thinking Log

 

Pendulum Thinking Log Fair Test Ideas: Arrange the cards in the envelop to create a concept map showing how

all the big ideas about FAIR TESTS fit together. Once you are satisfied that your arrangement

is meaningful and you have used all of the cards, copy your concept map in the space below

(or glue down the cards).

Pendulum Experiment Details and Diagrams: Draw your pendulum experimental set-up and clearly label all of the parts. Also label how

you will measure displacement.

Describe how you will measure displacement in your pendulum experiment? ______

__________________________________________________________________________

Describe how you will measure the mass of the pendulum bob in your experiment?

___________________________________________________________________

___________________________________________________________________

Describe how you will count one pendulum swing in your experiment? _________

___________________________________________________________________

Pendulum Experiment #1: Displacement (Release Position)

What is the independent variable? ______________________________

What is the dependent variable? _______________________________

Research question (What we want to discover): What is the effect of

displacement (release position) on the number of swings in 15 seconds?

Prediction (What do you think will happen?): __________________________

_______________________________________________________________

Add a unit to the displacement column to show how you are measuring

displacement.

Record the data for the constant variables in data table. (Only count FULL swings)

Do the experiment, then record the results in the data table.

Data Table 1: Release Position (Displacement) and Number of Swings

Number of Swings in 15 sec

Displacement

( ) Length

of String (cm)

Mass (number of washers)

Trial 1 (number of

swings)

Trial 2 (number of

swings)

Trial 3 (number of

swings)

Average (number of

swings)

 

Write a claim (conclusion) about what you discovered in this experiment.

________________________________________________________________

________________________________________________________________

Pendulum Experiment #2: Mass

What is the independent variable? ______________________________________

What is the dependent variable? _______________________________________

Research question: __________________________________________________

__________________________________________________________________

Prediction: (complete sentence) __________________________________________

__________________________________________________________________

Correctly label all columns and rows in the data table and add a title.

Record the data for the constant variables in data table.

Carry out the experiment then record the results in the data table.

Data Table 2: ____________________________________

Write a claim about what you discovered in this experiment. ________________

___________________________________________________________________

Pendulum Experiment #3: Length of String

What is the independent variable? ______________________________________

What is the dependent variable? _______________________________________

Research question: __________________________________________________

__________________________________________________________________

Prediction: (complete sentence) __________________________________________

__________________________________________________________________

Correctly label all columns and rows in the data table and add a title.

Record the data for the constant variables in data table.

Carry out the experiment then record the results in the data table.

Data Table 3: ____________________________________

Write a claim about what you discovered in this experiment. ________________

___________________________________________________________________

Write an overall claim about the variables that do and do not affect the rate of a

pendulum’s swinging. ________________________________________________

___________________________________________________________________

___________________________________________________________________

Cards for Fair Test Concept Map Activity:

Fair Test

Variables

Independent

Variable

Dependent

Variable

Research

Question

Trials

Claim

What I 

measure 

  

Things I can 

change in an 

experiment   

Constant

Usually do at 

least 3 trials 

  

What I 

choose to 

change 

  

Is a question 

that mentions 

both the 

independent 

and dependent 

variables 

  

Things I 

keep the 

same in an 

experiment 

  

The answer to 

the research 

question 

  

What I do to 

get good 

data.