SCIENCE SKILLS

WRITING A HYPOTHESIS

A hypothesis is an educated guess or a prediction of what is to happen in an experiment

Hypothesis should include the following:◦Opinion of what is to happen◦Evidence to support your opinion using data or

other information

Bad or Good Hypothesis

“The fish will not survive in the given temperature because fish need certain temperatures to live in order to function properly.”

“The fish will not survive in the given temperature.”

Writing a Hypothesis

Shannon wanted to test whether fertilizer would make her plants grow taller. Write a hypothesis for her.

“Fertilizer will cause the plants to grow taller because it will provide the plants with proper nutrients to grow.”

Data Analysis

When scientists analyze they want to identify trends or make claims/statements about what the data is saying.

When analyzing data:◦Make a claim or write a statement about what

the data says◦Support your statement with data from the

experiment

Data Analysis- Good or Bad

“The data says that girls are shorter than boys because on average the boys were five inches taller than the girls.”

“The data says that girls are shorter than boys

Data Analysis

Plant with Fertilizer

Plant with NO Fertilizer

Week 1 Growth 5 cm. 2 cm.

Week 2 Growth 4 cm. 3 cm.

Week 3 Growth 8 cm. 6 cm.

Data Analysis

“The plant that had fertilizer was able grew taller because during week 1 it grew 5 cm. and the plant without fertilizer only grew 2 cm. during the first week.”

“The plant that had fertilizer grew taller because on average it grew 4 cm while the plant without fertilizer only grew on average about 3 cm.”

Graphing

A graph is a visual to represent data.

Remember KEY things with graphing:◦Title- what EXACTLY is the graph about◦Labeling Axis◦Units◦Scale Properly◦Use Rulers◦Use the Correct Type of Graph

Graphing Titles- Good vs. Bad

“Number of DVDs Rented at MovieBuster Over the Course of 1 Week”

“DVDs Rented”

“Number of DVDs Rented in 1 Week”

Conclusion

A conclusion is what you write at the end of the experiment to summarize your findings.

What needs to be included:◦Hypothesis Restated- rewrite your hypothesis◦Support/Reject Hypothesis- did the data

support or reject your hypothesis◦Possible Errors◦ Improvements and/or next experiment

Conclusion

Next Steps in an Experiment:◦More Trials◦Different Brands/Substances

Possible Errors:◦Not enough data/trials◦Human Error- forgot to do something; didn’t

keep track of the time correctly

Conclusion-good

“In this experiment my hypothesis was that the plants with fertilizer would grow taller because fertilizer would provide the plants with nutrients. My data supports this hypothesis because the plants with fertilizer grew 1 cm. taller than those that did not have fertilizer (on average). Some possible errors could be that I could have done the experiment for a longer period of time or added more plants. My next experiment would be for 6 weeks instead of 3 weeks to see if I obtain the same data.”

Conclusion- bad

“Fertilizer will make plants grow taller.”