1. The Scientific Method A logical, problem solving technique

2. Objectives Learn the Steps of the Scientific Method
Explain the difference between dependent and independent variables
Define an control group
Explain what a valid experiment is and how to make a valid experiment more accurate

3. What is the Scientific Method?
It is the steps someone takes to identify a question, develop a hypothesis, design and carry out steps or procedures to test the hypothesis, and document observations and findings to share with someone else.
In other words, it’s a way to solve a problem.

4. Introduction to the Scientific Method
Identify a problem
Gather Information
Formulate a hypothesis
Design and Experiment
Record and Organize Data
Analyze Data
Draw Conclusions
Use conclusions to develop a new hypothesis

5. Scientific Method Problem/Question Observation/Research
Formulate a Hypothesis
Experiment
Collect and Analyze Results
Discussion/Error Analysis
Conclusion
Repeat
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6. Steps of the Scientific Method
Problem/Question: Develop a question or problem that can be solved through experimentation.
Ex. Does soil temperature affect plant growth?

7. Steps of the Scientific Method
2. Observation/Research: Make observations and research your topic of interest.
Use references to do background research
Books
Journals
Magazines
Internet TV
Videos
Interview Experts
Become Educated on your topic

8. Steps of the Scientific Method
3. Formulate a Hypothesis: (Educated Guess) Predict a possible answer to the problem or question. Using an IF, THEN statement
Example: IF soil temperatures rise, THEN plant growth will increase.

9. Steps of the Scientific Method
Experiment:
- Develop and follow a procedure.
- Include a detailed materials list.
The outcome must be measurable (quantifiable).
EX. The height of the plants in cm

10. Steps of the Scientific Method
5. Collect and Analyze Results: Make Charts/Graphs.
Compare and look for trends and patterns using graphs
“A picture is worth a thousand words”

11. Steps of the Scientific Method
6. Discussion/Error Analysis
Discussion
What variables were easily controlled?
How can the results be applied to real life?
What new experiments could be done using the knowledge gained from this one?
Error Analysis
What were the variables that were hard to control; contributing to uncertainty?
How could you improve the method to minimize the errors?

12. Steps of the Scientific Method
7. Conclusion:
Directly answer the question asked in the problem.
Include a statement that accepts or rejects the hypothesis and why.
Refer to your data in your explanation.

13. Steps of the Scientific Method
8. Repeat Experiment You must repeat the experiment to make it valid.

14. Results and Data
**** If your results DO NOT fit your Hypothesis DO NOT CHANGE YOUR DATA. Change your hypothesis and retry your experiment.

15. Think you can name all eight steps?
Collect and Analyze Results
Formulate a Hypothesis
Communicate the Results
Observation/Research
Problem/Question
Experiment
Conclusion
Discussion/Error Analysis

16. Variables: Independent Variable
The independent variable is the variable that the scientist changes or manipulates
The independent, or manipulated variable, is the variable that can be controlled by the experimenter.
It usually includes time (dates, minutes, hours), depth (feet, meters), temperature (Celsius).
This variable is ALWAYS graphed on the X axis
Examples:
The temperature of the soil
The “I” means whoever is running the experiment. This is the students

17. Variables: Dependent Variable
The dependent, or responding variable, is the variable that is directly affected by the independent variable. It is the result of what happens because of the independent variable.
Is the thing measured in the experiment
Changes because of the independent variable
“Depends” on the independent variable
This variable is ALWAYS graphed on the Y axis.
Example:
The amount the plant height changes with different soil temperatures
The plant height is dependent on the soil temperature
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18. Remember!!! Graphing
When graphing your data from an experiment always place the independent variable on the X axis (horizontal) and the dependent on the Y axis (vertical) .

19. Variables: Constant Examples:
All the factors in the experiments that are kept the same
Everything except the independent variable
Keeps the experiment ‘fair’
The amount of sun each plant gets
Type of soil
Type of plant
Amount of water
All plants are the same age

20. Control Group
In a scientific experiment, the control is the group that serves as the standard of comparison.
The control group is exposed to the same conditions as the experimental group, except for the variable being tested.
All experiments must have a control group.

21. Valid Experiment
In order for a scientific experiment to be valid it can only have 1 variable.
This variable is the part that is being tested.
All other parts of the experiment must remain the same or constant
Any experiment that has more than 1 variable cannot prove anything and therefore is invalid

22. More Valid/More Accurate
To make an experiment more valid:
Increase the number of test subjects
Repeat the experiment and get the same results
Have other people complete your experiment and get the same results (peer review)
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