Third grade math standards require students to represent and interpret data using visual organizers, including bar graphs. Third-graders are expected to understand how to draw the graphs and answer questions based on graphs. Lessons include teaching the parts of a bar graph, creating the graph and reading the graph to find data.
Parts of a Bar Graph
Third-graders need an understanding of the parts of a bar graph before they can accurately read and use this math tool. Draw a basic bar graph on the board as an example with labels for the different parts, including the title, axes, scale and bars that represent information. Point out the vertical and horizontal axes, including what information each represents. The horizontal typically represents the options, while the vertical shows the quantity. Show several bar graphs with different scales to help third-graders learn how to determine the quantity represented by each bar. For example, one graph might mark every number, while the lines on another might count by fives, 10s or 100s.
Bar Graph Interpretation
The third grade math curriculum typically includes solving problems using bar graphs. This might include one-step or two-step problems, such as finding the total or difference between different bars on the graph. Start with simple tasks. Ask students to find the number represented by each bar, for example. Move into problems that ask students to compare two different bars on the graph to see how one represents a greater quantity of the measured item. Increase the complexity of the problems as the students improve at interpreting the data.
Bar graphs become meaningful to third-graders when they collect data themselves. One simple way to do this is to have students vote. Ask a question, such as favorite ice cream flavor or how kids get home from school. Each student casts a vote for one of the answer options. You can also have students create their own problems and collect data on their own. A child might decide to make a bar graph on hair color in the classroom, for example. He would list his color options and count the number of kids in the class that fit into each color option. This lesson helps students understand where the numbers come from on a bar graph.
Bar Graph Drawing
Drawing a scaled bar graph is a typical third grade math standard. Use the data students collected to have them draw their own graphs. Graph paper works best because students can fill in squares based on the number needed in each bar. Provide a sample bar graph and review the components. Students draw the axes and include labels for each. They also decide on a scale based on the numbers they have in their data. Give the third-graders a chance to present their bar graphs and explain the data. Students can also come up with their own math problems and trade papers with a partner to practice interpreting the data.