I have a big class so stickers are used up rapidly. I make my own on my computer using address labels. I can make thirty on one sheet. I personalize some and adjust the message according to the students' ages and the subjects being taught. Of course, generic messages usually work the best. For example, I have an Einstein Award where I write, 'I was really thinking' next to a picture of Einstein. There's a lot of enthusiasm and competition to get the first award of the day.