I know the 100th Day of School is a big deal for many primary classes. They get to count 100 things, make 100 things, eat 100 things, and who knows what else. Now those of you who teach the upper grades can join the fun! This 100th Day of School Challenge printable will get your kids thinking in all kinds of ways. It requires a combination of creative writing, critical thinking, math, and research to complete. Use it at a center, as homework, or with the whole class.