Stage three: Experimental science project

Stage 3:
DESIGN AN EXPERIMENTAL PROCEDURE TO TEST YOUR HYPOTHESIS

Design an experiment to test each hypothesis. Make a step-by-step list of what you will do to answer your questions. This list is called an experimental procedure.

Guidelines for Experimental Procedures

• Select only one thing to change in each experiment. Things that can be changed are called variables.
• Change something that will help you test your hypothesis.
• The procedure must tell how you will change this one thing.
• The procedure must explain how you will measure the amount of change.
• Each type of experiment needs a "control" for comparison so that you can see what the change actually did.

OBTAIN MATERIALS AND EQUIPMENT

Make a list of the things you need to do the experiments, and prepare them. If you need special equipment, a local college or business may be able to loan it to you. Another source of science materials are mail order supply houses such as Edmund Scientific in Barrington, New Jersey (phone 1-609-457-8880 for a catalog). Professional science supply houses are located in larger cities. They will have just about anything you will need.

DO THE EXPERIMENT AND RECORD DATA

Do the experiment and record all numerical measurements made. Data can be amounts of chemicals used, how long something is, the time something took, etc. If you are not making any measurements, you probably are not doing an experimental science project.

RECORD YOUR OBSERVATIONS

Observations can be written descriptions of what you noticed during an experiment, or problems encountered. Keep careful notes of everything you do, and everything that happens. Observations are valuable when drawing conclusions, and useful for locating experimental errors .

CALCULATIONS

Perform any math needed to turn raw data recorded during experiments into numbers you will need to make tables, graphs or draw conclusions.

SUMMARIZE RESULTS

Summarize what happened. This could be in the form of a table of numerical data or graphs. It could also be a written statement of what occurred during the experiments.

DRAW CONCLUSIONS

Using the trends in your experimental data and your experimental observations, try to answer your original questions. Is your hypothesis correct? Now is the time to pull together what happened, and assess the experiments you did.

Other Things You Can Mention in the Conclusion

• If your hypothesis is not correct, what could be the answer to your question?
• Summarize any difficulties or problems you had doing the experiment.
• Do you need to change the procedure and repeat your experiment?
• What would you do different next time?
• List other things you learned.

TRY TO ANSWER RELATED QUESTIONS

What you have learned may allow you to answer other questions. Many questions are related. Several new questions may have occurred to you while doing experiments. You may now be able to understand or verify things that you discovered when gathering information for the project. Questions lead to more questions, which lead to additional hypothesis that can be tested.

WHAT IF MY SCIENCE PROJECT DOESN'T WORK?

No matter what happens, you will learn something. Science is not only about getting "the answer." Knowing that something didn't work, is actually knowing quite a lot. Experiments that don't turn out as planned are an important step in finding an answer.