Encourage a group of third graders to play this fun game of Whistle Hide-and-Seek as a warm-up to get them prepared for finding a "lost" camper.

Try this simple activity with your child to guesstimate the age of a tree in your yard and nurture her developing math skills while you're at it!

This interdisciplinary card game will have your third grader working on math facts as he travels through the solar system!