Scientific Method:  TB: Pages 1-11

Scientific Method

STEP 1 – IDENTIFY THE PROBLEM

-         This defines the topic you need to solve.

-         The problem needs to be in the form of a question.

 

STEP 2 – DO SOME RESEARCH

-         This can be from brainstorming

-         You can also find information from books, etc

 

STEP 3 – COME UP WITH YOUR HYPOTHESIS

-         This is an educated guess

o      It’s “educated” because it is based on the research

-         Must be in the form of a statement

o      “As this happens, that will happen.”

-         Use the variable names in your hypothesis

 

STEP 4 – CONDUCT YOUR EXPERIMENT

-         follow a procedure

-         collect data in an organized way

-         identify your variables (*see below)

 

STEP 5 – DO THE ANALYSIS

-         look at your data

-         try to find trends

 

STEP 6 – WRITE A CONCLUSION

-         briefly review what you did

-         refer back to your hypothesis

o      Was it right or wrong?

-         discuss possible errors

o      There are always some errors that can be fixed

 

 

*Parts of an experiment:

• Procedure - detailed steps needed to perform an experiment
• Independent variable - "I" change this; changed by the experimenter
• Dependent variable – “D”ata being collected; changes as a result of the independent variable
• Constants - remain the same for all trials in an experiment
• Control Group – “normal” group; group used for comparison; is not experimented upon; does not receive treatment
• Experimental Group - group(s) that part of the actual experiment; involves changing of independent variable

Example Experiment:

A group of students wanted to know if eating candy would help them do better on tests.  They decided to run an experiment to test it out.  They all agreed that sugar gives them energy so they thought having candy would help.  They looked at the labels and saw that the Life Savers would have the most sugar if they ate a certain amount of them, so they decided that it would work the best.  Cara started by creating four quizzes that they would take.  The five students in the group all took the first quiz and they all scored about the same.  Then for two weeks they carried out the experiment.  Fred did not eat any candy during that time.  Gina ate Twizzlers every day while she was studying.  Derek ate Life Savers every day while he was studying.  Leira ate 3 Musketeers bars every day while she was studying.  Cara was in charge of giving them things to study and then to give and grade the quizzes.  After two weeks Cara gave them the next round of quizzes and then she graded them.  Fred had the highest score of them all by a whopping 10 points!  His score was a 93.  Leira scored an 83.  Derek scored an 82 and Gina scored an 80.  They wondered if it was a valid result so they planned to keep running the experiment for another two weeks and then Cara would give them the next quiz.

Answer the following questions based on the story above.  (Note: you can highlight the empty spaces between questions to see the answers.)

1. What was the hypothesis?
   Life Savers would have the best effect on quiz scores.
2. What is the independent variable? 
   The group changed the type of candy.
3. What is the dependent variable?
   They measured their quiz scores as a result.
4. What are some constants?
   They took the same quizzes.  They tested on the same information.  They studied for the same amount of time.
5. What is the control group?
   Since Fred did not eat candy, his results made up the control group.
6. What are the experimental groups?
   Derek, Leira, and Gina made up the experimental groups because they had candy.
7. Was the hypothesis correct?
   No, the group without any candy scored the highest on the quizzes.