Use this simple, but eye-catching graphic as a sheet on which children can count, sort, and glue or draw 100 objects divided into sets of 10. A handy reproducible for 100th day. 

Scholastic has put together 100th day math ideas from several different teachers. Includes "zero, my hero", probability, sorting, measuring, estimating, counting, weighing, money, and other ideas for celebrating the 100th day.

Great ideas for "100th Day" activities. Most of these would be a good challenge for upper elementary school students if you want to include them in your 100th Day celebration. Activities include counting, measuring, weighing, sorting,...

Scholastic.com provides a reproducible coordinate grid activity on a 100 grid to help your students celebrate the 100th day of school.