Have the students indicate their favorite juice by choosing a like-colored connecting cube, for example, red for tomato juice, orange for orange juice, yellow for apple juice, and purple for grape juice. Record this data on the chalkboard.
Then ask four volunteers to each collect all the cubes of one color and snap them together. Place the connected cubes side by side to form a bar graph. Then ask such questions as “How many more children liked orange juice best than liked grape juice best?” Encourage children to pose related questions and call on classmates to answer them. Then model for the students how to translate the cube graph to a graph on paper. You may wish to model the bar graph on overhead graph paper.
The example below shows the following results:
tomato juice (2), orange juice (8), apple juice (10), and grape juice (6).
Encourage students to draw the bar graph on their own graph paper.
Students should record, on paper, some questions that they answered from the bar graph.
Next, open the
Bar Grapher Tool and project for students to see. This tool allows you to enter your own data and graph it, or you may use preselected data and graph it. Create a bar graph for students to view. Once you have created the bar graph, pose questions which require students to use subtraction to compare. (Note: It would be best if you enter your own data for this class example, so the numbers are whole numbers and are relevant to the students' lives.)
