For our 100th day trail mix we used popcorn, small Ritz crackers, pretzels, small Teddy Grahams, marshmallows, m&ms, Cheerios, Fruit Loops, mini Oreos, and packs of fruit snacks that had 10 pieces in them. Each student got to take 10 of each item so they had 100 pieces in their trail mix. If the students did not like an item I let them pick one of the other items.
Below are pictures of a fun 100th day project we do. We ask the parents to send in black yard sale dots. Each student gets 100 dots. We talk about what type of picture we can make using the dots. The students got to pick white or black paper. This year I used the small construction paper because I wasn't thinking, usually I have them do it on large construction paper. They have to use all 100 dots to create a picture.