Scholastic
Scholastic: Celebrate the 100th Day of School
This resource presents many 100th Day activity ideas. They are listed by the following subject areas: language arts, math, social studies, science and even a just for fun section.
A to Z Teacher Stuff
A to Z Teacher stuff.com: 100th Day of School
How can you plan an exciting and educational 100th day of school for your students? The answers can be found in this comprehensive resource. This site features activities, lesson plans, songs, poems and more.
Other
K 3 Learning pages.com: 100th Day of School
This site features several links for kindergarten through third grade resources for the 100th Day of School. These links include activities, songs, poems and more.
Other
100th Day of School Activities
These mostly math-related activities are for elementary teachers to celebrate the 100th day of school.
abcteach
Abcteach: 100 Days of School Poem
The PDF document features a poem about reaching the 100th day of school.
Enchanted Learning
Enchanted Learning: Crafts for Kids
Choose from dozens of simple crafts including activities for the holidays, animal crafts and much more.