Using Race Times To Teach Averages

Today we had the students determine their average time for the 50 yard sprint. One student would time while the other ran. Each students had several opportunities to be the time keeper. The student would run and be timed for three races. The students in 4th and 5th gave us the average time. Students in 3rd grade were asked,"If it takes you 12 seconds to run to point a and then back, how long does it take you to run to just point a?" The students gave varying answers such as 6 because 6+6=12 and 6 times 2 equals 12. Grades 1 and 2 were able to learn how to write the time the correct way and what it meant.