The Scientific Method

The Nine Steps of the Scientific Method

1. Questioning

2. Controlling Variables

3. Making a hypothesis

4. Planning

5. Performing

6. Observing

7. Analyzing

8. Evaluating

9. Communicating

1) Asking a question• Semi-formal• Similar to brainstorming• Question should interest you• Question can be about anything• E.g. Are taller people better at basketball than

shorter people?

2) Controlling the variables• Variables are factors that can affect the outcome

of an investigation:

1) Independent variable – variable that is changed

2) Dependent variable – variable that is affected by the independent variable

3) Controlled/Standardizing variable – variable that remains unchanged and does not affect the outcome

4) Control Group – Group that is not changed, normal conditions used to compare results

3) Making a hypothesis• Is a tentative answer about the outcome of a controlled

experiment along with an explanation for the outcome• Should be presented in an “if / then / because”

statement• Should indicate cause and effect relationship• Can usually be derived directly from your original

question• Is an educated guess• Should be only a single sentence• Must be feasibly testable• E.g. If someone is taller then they will be better at

basketball because they are closer to the net.

4) Planning• Identify all your variables

• Consider equipment and materials

• Write a clear procedure

Writing a procedure• A procedure is a sequential list of steps

that are to be followed exactly during an experiment. Steps should be in order and numbered.

• Hints: Be specific, be exact, watch your language.

• Try this:– In a group of 2, write up a procedure for

washing your hands. Starting from dry and hands and ending with dry hands.

5) Performing the experiment

• Follow procedures exactly, if procedures are unclear ask

• Be safe• Record which variables are being changed and

how they are being changed• Repeat experiment a minimum of three times.

(Why?)• Make careful notes of everything that occurs

during your experiment, in addition to the data filling in charts and tables. Note possible sources of error

6) Observing and recording data• Record all data/observations in an appropriate

form. (Charts or tables are most common)• Record all data as clearly and accurately as

possible• Make careful notes of everything that occurs during

your experiment, in addition to the data filling in charts and tables. Note possible sources of error

• Note anything that happens the same or differently each time, as well as anything that might have changed from one experiment to the next

• Note possible sources of error in the experiment

7) Organizing and analyzing results

• When possible create graphs to represent numerical data, as it is easer to read and understand for others

• Identify patterns and trends in results

• Make conclusions

• Determine if your hypothesis is supported by the results

8) Evaluating/Conclusion• How useful is the evidence?

• Determine if your hypothesis was correct

• Share your process and finding with others by writing a report

9) Communicating