Explain to the students what the box and whisker plot is and what it does. Tell them that the five-number summaries include the median, quartiles and the smallest and greatest values from the number distribution.
Give each child a pencil and paper and a series of about 13 numbers, such as 54, 23, 17, 98, 87, 13, 10, 22, 99, 34, 86, 37 and 58. Have all children find the median of the numbers by ordering them from lowest to highest. In this case, the median is 37.
Have the children find the lower quartile of the numbers. Circle the numbers to the left of the 37 and find the median of those numbers, in this case, 22.
Find the upper quartile using the same method. In this set of numbers, the upper quartile is 86.
Draw a number graph from 10 to 100. Draw a box on top of the graph containing the lower quartile, the median and the upper quartile at the appropriate areas on the graph. Place the lowest number outside the box on the graph and the highest outside the box as well. These are the five summary data numbers that help interpret the number data.
Instruct the children to practice making the graphs until they are proficient in box and whisker plotting.