The Scientific Method

The Scientific Method • The Scientific Method is a systematic approach to PROBLEM SOLVING.

Scientific Method Steps • STATE THE PROBLEM /gather information • Form a hypothesis • List materials • Write a procedure to test my hypothesis • Conduct the experiment • Record and analyze data collected • Draw a conclusion

State the problem • The problem you are trying to solve is stated in the form of a QUESTION. • Investigate a problem that interests YOU!! • Example: A gardener might ask… • Which fertilizer works the best on bean plants?

Gathering Information • Make OBSERVATIONS and INFERENCES on your problem. • Think of any prior experiences that you have had that could help. • Example: • The gardener has used Wal-Mart brand before and the plants did not do well. He also used Miracle Grow and it worked better, but not with bean plants.

Observation: Using your five senses to gather information…sight, touch, hearing, taste, and smell Ex: ) The fruit is sticky and orange in color • Inference: A logical explanation of what happened…An inference is correct as long as it makes sense!! Ex: ) An apple core sits on the plate besides Dexter. He finishes wiping his hands and puts a napkin on a plate…What can you INFER?

Forming a Hypothesis • A hypothesis is an educated GUESS or possible solution. • Should be written in an “IF…THEN…”format. • Your testing will be based on your HYPOTHESIS. • You will be proving it RIGHT or wrong. • Example: • If I plant several bean plants in various fertilizers, then the miracle grow plant will grow the tallest.

Materials • Before beginning your EXPERIMENT, you must create a list of MATERIALS that you will use. EXAMPLE Materials: • 3 bean seeds, 1 cup Miracle Grow, 1 cup Wal-mart brand fertilizer, 1 cup Fertilizer X, three 5 in. deep pots, measuring cup, water, sunlight, ruler, paper, pencil.

Procedure • You need to list ALL steps that you plan to execute during your experiment. This is your PROCEDURE. The procedure should read like a set of directions. • EXAMPLE Procedure: 1. Gather all materials listed above. 2. Fill each 5 in flower pot with 1 cup of each of the 3 types of soil. 3. Place one bean seed 3 cm. deep into each type of fertilizer. (ETC…and so on until you complete all steps listed.)

Testing the Hypothesis • The experiment should test the HYPOTHESIS. • Within you experiment, you include the following: • INDEPENDENT a.k.a MANIPULATED variable– the factor that the scientist changes. (Remember I’m for independent/manipulated) • DEPENDENT a.k.a RESPONDING VARIABLE – the factor that is expected to change because of the INDEPENDENT variable. (Remember Dr. for dependent/responding)

Testing the Hypothesis (cont.) • In the fertilizer problem example: Manipulated a.k.a ____________ variable is the type of fertilizer we are using, because we change or MANIPULATE those within the experiment. Responding a.k.a ____________ variable is what HAPPENS to the plant BECAUSE of the changes we made (the manipulated variable). So…What happens to the plant????

Testing the Hypothesis (cont.) • Controlled Experiment – an investigation in which the factors that influence the outcome are kept the same EXCEPT for the one whose effect is being studied. • Constants –All other factors which remain the same throughout the experiment except the one whose effect is being studied. • Example: • In our fertilizer experiment we would use the same: type of plant, temperature, amount of water, amount of sunlight. We would ONLY change one thing…the ______________.

Recording the Data/Results • Recording all observations and MEASUREMENTS. • Just the facts. • Type of data to use: • QUALITATIVE: L= letters. Descriptions such as color, odor, sounds, etc. Example: The green plant. • QUANTITATIVE: N = numbers. Measurements. • Data can be shown in the form of GRAPHS and tables; both are visual displays.

Recording the Data/Results (cont.) • Example: What’s going on in this graph?

Conclusion • This is a SUMMARY of your investigation. • You MUST include or check for the answers to the following questions: • 1. What do your results tell you about what you have investigated? 2. Was the hypothesis correct? 3. Is there some type of pattern? 4. How well does your graph in the results section show your date? Are the results clear? 5. Anything that you would do differently to improve your experiment? 6. Is there any data that does not “fit” the normal pattern? Could it be a mistake?

Conclusion (cont.) • Example: During my experiment to test the 3 different types of fertilizers, Miracle Grow helped the bean plant grow the fastest. Wal-mart brand was the second best and Fertilizer X was the least effective fertilizer. My hypothesis was correct because I thought Miracle Grow would work the best. I tried really hard to have controlled experiment and I made sure to keep everything like the amount of sunlight, amount of water, amount of fertilizer, etc. the same. The only thing I changed was the type of fertilizer. The data seems to follow a normal pattern, so I do not think I made any mistakes. To improve this experiment, next time I will use more types of fertilizer to see which one really is the best.

The Scientific Method