1. Doing Science: The Scientific Method
Chapter 1-2
Science 8

2. What are two types of research? Descriptive research
Solve problems by observation
Experimental research
Solve problems by testing hypothesis through use of carefully controlled steps

3. List the steps of descriptive research.
Research objective
What you want to find out
Research design
How investigation will be carried out
How data recorded and analyzed
Bias
Avoid bias
Careful measurements
Random samples

4. What are steps of experimental research design? Scientific Method
Step-by-step approach to help scientists find solutions to problems

5. What are the steps of the Scientific Method?
Purpose
Hypothesis
Experiment
Analysis
Conclusion

6. Step 1. Purpose “What do I want to find out?” Questions come from:
Reading an article in a book or magazine
Interesting observations
Thought about a scientific phenomenon
Conclusions from another experiment

7. Purpose of the experiment should be specific
Problem should be something that can be solved through experimentation
What is the average number of seeds found in apples?
Does the color of a surface affect it’s temperature?

8. Practice Time
Identify if the following questions would be appropriate for scientific investigation.

9. Which has more fries—a large McDonald’s French fry or a large Sonic French fry?
What is the average number of pine cones on a branch of a pine tree?
What happens if you do not eat breakfast?

10. Step 2. Hypothesis Idea to a solution for a problem Educated guess
Based on knowledge/research
“This is what I think will happen.”
Written as an “If…then…”statement
“if” is the part the scientist will change on purpose
“then” is the result of the change

11. Hypothesis examples.
IF fertilizer is added to a plant, THEN it will grow taller
IF a player attends batting practice, THEN their batting average will improve.

12. Practice Time!!
Write a testable hypothesis for each of the following questions.

13. How does advertising for the aluminum can collecting week affect the number of cans collected?
If we advertise for the aluminum can collecting week, then we will increase the number of cans collected.

14. How does the depth of a lake affect it’s temperature?
If we measure the lake at different depths, then we will find that the temperature decreases as we get deeper.

15. Step 3. Experiment Testing of the hypothesis to see if it is correct
During an experiment, the following must be done:
Decide which variables and controls will be used
Control—standard that you apply to all parts of the experiment (does not change)

16. Independent variable—variable that you purposely change (what’s being tested)
Dependent variable—variable that is being observed (what’s being measured)

17. Practice Time!!
Identify three possible variables for the following situations.

18. Determine length of experiment
Repeat to verify results
Be a good observer
Measure exactly

19. Step 4. Analysis “What happened during the experiment?”
Data is collected and observation are made during the experiment
Numerical data—height, weight, temp…
Verbal data—words to describe observations
Any problems with the experiment are noted along with errors that occurred

20. Scientists will tell what was learned from the experiment
Step 5. Conclusion
What did I find out?”
Scientists will tell what was learned from the experiment
Did the results confirm hypothesis
Did the results deny hypothesis
Are there any more questions to answer
Brief statement that summarizes the key points and outcomes of the experiment