1. Steps in the Scientific Method
Observation
Hypothesis
Experiment
Data Collection
Conclusion
Retest

2. Solving a Problem 1)Identify a Problem
2) State Observations about the problem
3) Form a Hypothesis about the problem (if…then…)
4) Design an Experiment to test the hypothesis
5) Collect Data
6) Form a Conclusion
7) Retest

3. A good or “valid” experiment will only have ONE variable!

4. Controls and Variables

5. Scientific Experiments Follow Rules
An experimenter changes one factor and observes or measures what happens.

6. The Control Variable
The experimenter makes a special effort to keep other factors constant so that they will not effect the outcome.
Those factors are called control variables.

7. What is the Purpose of a Control?
Controls are NOT being tested
Controls are used for COMPARISON

8. Other Variables
The factor that is changed is known as the independent variable.
The factor that is measured or observed is called the dependent variable.

9. Example of Controls & Variables
For example, suppose you want to figure out the fastest route to walk home from school.
You will try several different routes and time how long it takes you to get home by each one.
Since you are only interested in finding a route that is fastest for you, you will do the walking yourself.

10. What are the Variables in Your Experiment?
Varying the route is the independent variable
The time it takes is the dependent variable
Keeping the same walker throughout makes the walker a control variable.

11. Remember: To be a Valid Experiment:
Two groups are required --- the control & experimental groups
There should be only one variable

12. Data Results of the experiment May be Quantitative (numbers)
Qualitative
Data that cannot be measured.-descriptions Colors, textures, appearance

13. Data
Must be organized
Can be organized into charts, tables, or graphs

14. Line Graphs
5/3/2019

15. What is the difference between a bar graph and a line graph?
Bar Graph vs Line Graph
What is the difference between a bar graph and a line graph?

16. 5/3/2019

17. What can time be measured in???
Line graphs:
graph used to show change over time.
What can time be measured in???
Seconds - Minutes - Hours – Days - Weeks - Months – Years - Decades - Centuries - etc.

18. Would we use a line graph in the following situations:
When to use a line graph?
Would we use a line graph in the following situations:
To show how many people like pizza in this class? NO
To show how much it rained each month this year?
YES- because months and years deal with time.
To show how many people go to Chic-Fil-a on Friday? NO
5/3/2019

19. How do we make a line graph?
A line graph ALWAYS has a title!
A line graph has two different axis’s
Horizontal line (called x axis) or
Vertical line (called y axis) Y X
                     

20. X-axis and Y-axis
The x and y-axis usually starts with zero on a line graph
It is important to make sure that the intervals on our y-axis are always equal.
What does this mean???
5/3/2019

21. Intervals Make sure that you use a congruent number system Example:
2, 4, 6, 8, 10
5, 10, 15, 20, 25
5/3/2019

22. Plotting a Line graph Independent variable Dependent variable
on the X (horizontal axis).
Dependent variable
on the Y (vertical axis).
Time in minutes
5/3/2019

23. Use the following information to make a graph.
Make your own…..
Use the following information to make a graph.
Remember to read the information carefully and label everything!
5/3/2019

24. Mr. Tyler’s Height Age Height (inches) 5 40 inches 10 48 inches 1520
74 inches 25
75 inches
5/3/2019

25. Mr. Tyler’s Height
Mr. Mamula’s Age

26. Lets Try Another One Cost of a Teddy Bear 2010 $15 2011 $25 2012 $35
2013
$95
2014
$85
2015
$30
2016
$10
5/3/2019

27. Cost Of Teddy Bear
5/3/2019
Year

28. Is the information the same on both graphs?
5/3/2019