Lesson 3 The Meaning of the Mean

The students in Mrs. Dewey's class are preparing for the Bessie Coleman School Olympic Day. They want to wear sweatbands during the races. To order the sweatbands, they need to know the average head circumference of students in the class.

The class first worked together in groups of four students. They measured the distance around each person's head. Then, they found the mean circumference for each group.

Finding the Mean Circumference

Work with a group of four people to complete the same activity.

Measure head circumference with strips of paper:

• For each member of the group, wrap adding machine tape around the student's head.
• Mark the distance around the head with a crayon.
• Cut the adding machine tape at the crayon mark to make a strip that is the same length as the circumference of the student's head.
• Check the strip. Wrap it around the student's head again. The ends of the strip should just touch each other.