Let your students make something special to wear to celebrate the day. Make glasses that look like the number 100 or make a 100th day hat. Give each student a sentence strip and have him write the number 100 on it. Measure the sentence strip to fit around the child's head and then staple it to make a headband. Give the students small stickers to use to decorate it. Show them how to put the stickers into groups of 10 so that they can be sure they have 100 stickers on their hats.
Another activity is a Fruit Loops cereal necklace. Give each student a long piece of yarn or string and show them how to string cereal pieces on it to make a necklace. Tell them to use 10 groups of 10 pieces of cereal to make a 100-piece necklace.
Give each student a book of 10 pages of blank paper stapled together. Have her draw or stamp 10 things on each page to make a book of 100 things. You can also use stickers for this project.
Let your students work in small groups to make towers of 100 snap cubes. Have the students first make 10 towers of 10 cubes each and then snap them together to see how long is 100 cubes.
Have your students draw pictures of what they think they will look like when they are one 100 years old.
Give each student a paper with the sentence "I wish I had 100 _________." written on it. Have them complete the sentence and illustrate it. Another idea is let each student tell you what she would buy with $100.
Let your students make their own 100th day snack trail mix. Place bowls of 10 different foods on a table and let your student come up a few at a time to put 10 of each food into a plastic bag to make a trail mix with 100 items. Some ideas for the trail mix are raisins, goldfish crackers, Cheerios, chocolate chips, M&M's, Chex cereal, pretzels, Skittles, peanuts and small marshmallows.
Here are three books about the 100th day of school that you can share with your students.
"The 100th Day of School" by Angela Shelf Medearis and Joan Holub tells how one class celebrates the 100th day of school.
"Miss Bindergarten Celebrates the 100th Day of Kindergarten" by Joseph Slate and Ashley Wolff follows a kindergarten class as each member plans to bring 100 of something wonderful into school for a celebration.
"Emily's First 100 Days of School" by Rosemary Wells is about a class that makes a new number friend every day for the first 100 days of school.