Illustrative Mathematics
Illustrative Mathematics: Choral Counting Ii
Using a 100 chart, learners will chant the counting sequence starting with one to one hundred. Variations can include skip counting, counting from various numbers other than one, and counting backward.
Illustrative Mathematics
Illustrative Mathematics: Start Stop Counting
Get your students moving with this fun counting game. Pick any number between one and one hundred and students will practice counting forward or backward with this "Duck Duck Goose" type game.
Starfall
Starfall: Pop Bubbles
In this learning game children are directed to pop 100 bubbles which are counted down as they pop the bubbles.
Other
Teachers first.com: 50 Ideas for the 100th Day of School
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,...