Science Skills: Making Bar GraphsName:______

Part 1: Practicing making bar graphs

Here is a sample data chart:

Favorite Color / Number of Students
Red / 22
Blue / 15
Green / 11
Black / 5
Pink / 2

1. Look at your data to determine how big your bar graph should be and whether horizontal or vertical bars will fit better on your paper. Decide the scale your bar graph will have. This is determined by the biggest and the smallest numbers in your data set. In the data from our example, the biggest number is 22; the smallest is 2. In this case, a scale showing multiples of 5 makes creating and reading the graph easier. Label the scale on your graph.

2. Decide how wide the other axis should be to show all of the type of data (5 colors in this case). Label this axis of your graph.

3. Draw the rectangles the right length to represent the data. Pick a good width for the data bars. Color coding can make a graph easier to read.

4. Give your graph a title.

Part 2: Taking a survey

Come up with a simple question like the example “What is your favorite color?” – something that will be easy to tally.

Write the question on a piece of white paper and hang your question on the wall. Each of you will go around and write your answers to each other’s questions.

Part 3: Tally your data.

Make a data chart like the one for “What is your favorite color?”

Part 4: Graphing

Make a bar graph of your data.

Bar Graph Warm UpName: ______

Bar graphs are great for looking at differences amongst similar things. Let's say we want to look at the number ofpieces of different kinds of trash found at the beach. We want to know whichkinds are found themost often and the least often.

Bar graphs are great because you canline up different typesof things right next to each other and compare them instantly.For example,the kinds of trash found are lined up on a horizontal axis in the bar graph below.The numbers indicatingpieces of trash found are lined up on avertical axis. The height of eachbarcan tell you the number ofpieces of trash of that kind that were found.Bar graphs are good for giving a comparison of absolute numbers.

1. What data is on the horizontal axis? ______

2. What data is on the vertical axis? ______

3. What kinds of trash were found? ______

4. Which trash was found the most? ______Approximately how much? ______

5. Why do you think the person who made this graph used “other” instead of listing the other trash items?

6. What kinds of trash have you seen on the beaches around here?