1. Graphing

2. Parts of a Graph Title – What is the graph about?
X- axis – usually the Independent variable (what is being compared or changed) WITH UNITS
Y- axis – usually the Dependent variable
(what is being measured – the numbers) WITH UNITS
Data – information being observed

3. Bar Graphs
Used when data is a one time measurement. This means that each variable is not measured continuously. (Qualitative)
Used to compare different types of events or ideas in the same conditions.
Examples: Activities vs. participants, light conditions vs. plant growth.

4. Data Table for Bar Graph
After School Activities
Number of Students
Watch TV 40
Talk on the phone 50
Hang out with friends 38
Complete homework 16
Earn money 35

5. Line Graphs
Used to show patterns and trends over a period of time. (Quantitative)
Connects the data points to help show those changes.
Examples: Temperature changes, population growths

6. Data Table for Line Graph Average Rainfall
Time (Months) 2 3 4 5 6 7 8 9
Rainfall (mL) 15 21 28 24 16 1

7. Comparative Line Graphs
Used to compare two or more sets of data.
These graphs will have the same labels, but different sets of data on them. Each different data set needs to be in its own color with a legend.
Examples: Comparing the average temperature for each month over a few years, a student’s grades in four subjects throughout their junior high experiences.

8. Data Table for Comparative Line Graph
Number of Science Majors in College
Year
1967
1977
1987
1997
2007
# of Females
100
250
300
600
650
# of Males
750
700
550

9. Circle Graphs Used to illustrate different parts of a whole unit.
The graph is usually color coordinated with a legend, and the percent of each unit written in the graph.
Examples: Number of blue, green or brown eyed students in the class, amount of spending money in a family budget.

10. Graph this data Day 1 2 3 4 5 Total Growth of plant 4 cm 6 cm 10 cm

11. Graph this data
An experiment was performed to measure the pH level of the soil when a plant was given different levels of light to grow.
Different light levels were accomplished by placing mesh screens over the light source. (more screens=darker)
Set up a graph and label the x-axis and y-axis of the graph.

12. Graph this data
The following data was collected for the previous experiment. 2 plants were used for each light level.
Light Level
Plant #
pH of soil
0 screens 1
6.5 2
6.1
2 screens
6.9
7.5
4 screens
7.3
7.7