Happy 100th day of school! It's a great time to take stock of all that you have learned and how far you and your class have come since day one together—and what's a party without a good costume theme?
Try one of these 100 days of school dress up ideas with your class to celebrate the big 1-0-0.
100th day of school costume ideas and outfits
Count to 100
One idea is to attach 100 of something to a T-shirt. Get counting with...
Cotton balls!
Feathers!
Pom-poms! Or use anything that can easily be counted out and attached to a shirt, such as googly eyes, puzzle pieces, or stickers.
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Be 100x loveable
Put your relationships with your students first by wearing 100 of their favorite things. 1st grade teacher Carly Robertson talks to her students about their favorite things and then incorporates them into her 100th day of school outfit.
Practice self-love by having your students pick 100 photos of themselves to create a wearable collage of their many faces and expressions!
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Go old school
What would life be like at 100? How do you think you would look? The 100th day of school is the perfect opportunity for your students to explore that they might look like when they are 100!
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100th day hats and more
Decorate paper hats with the number 100, memories of the last 100 days, or by drawing 100 of something.
Once you and your students are all in your 100th Day of School outfits, take a photo together to commemorate 100 days!
Have more 100th day of school outfit and costume ideas?
If you have more 100th Day of School dress-up ideas for teachers or students, share your ideas with us on Facebook, Instagram, or via email at shaped@hmhco.com.
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For more ways to celebrate the 100th Day of School with your students:
- 100th Day of School Activities: 11 Ways to Celebrate in the Classroom
- Challenge Your Students With These 100th Day of School Math Activities
Find more lesson plans and classroom resources on Shaped.
This blog, originally published in 2021, has been updated for 2025.
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