The Scientific Method - is an orderly and systematic way of problem solving

STEPS 1 – Ask a QUESTION (State the PROBLEM) * What is it you want to find out or investigate? *Your question must be able to be scientifically investigated *example: “What time do crickets make the most noise?”

In order to perform an experiment, the question you ask must be able to be scientifically investigated. Look at the statements below. Can they be investigated scientifically? (Yes/No) 1)Snakes travel in pairs. 2)Taking something that belongs to another person is wrong. 3)Animals behave in strange ways before an earthquake. 4)People who don’t recycle should pay fines. 5)Basketball is a better sport than soccer. 6)You will remember best whatever is read just before falling asleep. 7)A Schwinn bicycle is faster than a Huffy bicycle. 8)Trucks use more gasoline than cars. 1)Yes 2)No 3)Yes 4)No 5)No 6)Yes 7)Yes 8)yes

2 – RESEARCH the problem * What information can you find out about your problem? *example: research any previous studies on crickets

3 – Develop a HYPOTHESIS * A HYPOTHESIS is an educated guess about what you think may happen * It is written in an “If……...then…...” format CAUSE EFFECT * It must be TESTABLE! *example: “If it is 11:00 p.m., then the crickets will chirp the most often.”

More examples: “If it is dark, then crickets will chirp more often” This is a testable hypothesis written in the proper format. “If I have roses and daisies, then people will like daisies more than the roses.” Even though it seems to be written in the proper format, it is NOT a testable hypothesis because it is subjective when people’s opinions are involved.

Situation 1 A NASA engineer wants to see if salt will reduce the amount of ice and snow buildup on the runway. She spreads 200 lbs of salt on a test runway and simulates an airplane landing by using test equipment. She then repeats the test on a runway without applying salt. Hypothesis: If _______________________________________ then ______________________________________ situation 2 The tree house detectives want to see if different smells travel at the same speed. They spray a can of hairspray, peppermint air freshener, and insect repellant at the same time. Six friends stand around them in a large circle, five feet from the center of the circle where the three tree house detectives stood. Hypothesis: If _________________________________________ then ______________________________________

1)Using the same amount, which dish detergent would wash more dishes, Palmolive or Ajax? 2)Does sugar dissolve better in cold or hot water? 3)Can a fish live in water that is 130 degrees Fahrenheit? 4)Will a plant grow in a dark closet? 5) Does the size of a toy car’s wheels affect the rate at which it travels? Write a hypothesis using the If….then….. Format for the following questions.

4 – Design an EXPERIMENT *Plan and conduct an experiment to prove or disprove your hypothesis *It should be a controlled experiment – only one variable is changed at a time *example: I will count the number of chirps for five minutes at the top of each hour.

Design an EXPERIMENT (cont) *operational definition – is a statement that describes how to measure a particular variable (or define a particular term). For example: the speed of the toy car will be measured in cm/sec control group – the group, or subjects, that do NOT get the manipulated variable. It is used for comparison. For example: the toy car with the original wheels

Manipulated Or Independent *The variable that is changed ON PURPOSE *What did you DO? *If…….. (cause) Responding Or Dependent *The variable that changes BECAUSE of (or in response to) the manipulated variable *What HAPPENED? *Then…….. (effect) Controlled *These are the variables that were NOT CHANGED *What stayed THE SAME?

5 – OBSERVE and RECORD data * Watch what happens in your experiment * Write down your findings in an organized format * DATA – facts, figures and other evidence gathered through observations *example: set up a chart and record the time and the number of chirps

6 – ANALYZE your data * What does all your data mean? *What information is it giving you? *example: The chart shows that at 10:00 p.m. there were the most chirps

7 – State a CONCLUSION * This is a summary of your findings *You state whether your hypothesis was correct or not *example: According to my data, the crickets chirp the loudest at 10:00. My hypothesis was incorrect.

8 – REPEAT if necessary *Scientists always repeat their experiments to confirm their findings or test a new hypothesis