Students must understand that line graphs show change over time. At the seventh-grade level, instruct students to construct double-line graphs. They can research and graph average monthly local temperatures and temperatures of a place they would like to visit. Have them draw the resulting lines on the graph in two different colors.
Give each group two or more different-sized rubber balls. Students drop the balls from various levels: 50 cm, 100 cm, 150 cm and 200 cm. They record the height of the ball when it bounces from the various levels. Follow the same procedure for subsequent balls, and graph the comparison.
Students must know how to draw angles and calculate percentages prior to creating circle graphs. They can take random samples before school or during lunch to determine their peers' favorite middle-school classes. They calculate the percentage and draw each favorite class's portion of the 360-degree circle.
Math teachers often require students to keep track of their homework scores. Since stem and leaf plots display data from least to greatest, they fit well into this activity. Students can discuss average scores, range and outliers based on this information.
Students create scatter plots to determine the relationship between two data sets. Provide puzzles of varying difficulty levels and number of pieces. Students work in groups and record the time it takes to complete each puzzle. They plot the puzzle types and times it takes to complete them to determine the correlation.
A histogram displays data in numerical intervals. Survey students to determine how long they studied for the last math test. Create a horizontal line on the board of interval ranges. Ranges might include zero to 15 minutes, 16 to 30 minutes, 31 to 45 minutes and 46 to 60 minutes. Have each student write his time on a sticky note and place it vertically in the correct range on the board. Choose students to draw boxes around the resulting data.
This is can be one of the most difficult graphs for seventh-graders to comprehend. An effective procedure is creating a human box and whisker graph in which students become part of the plot. They represent the median, the upper and lower extremes and the upper and lower quartiles. Carol Shields presents a detailed example of this activity on the Blue Ridge Public Television website.