What is a good whole classroom gift for a second grade class?

I am about to come to the ending of my twelve weeks of student teaching in a second grade elementary school classroom. I want to get them a littel something either to all of them or as a whole class. What do you think is a good idea, but not to high in price?

~~~years ago my daughter had such a wonderful student teacher,,,,he really gave them the gift of wanting to learn and loveing to read. At the end of his stay,,,he made each student a card, thanked them for letting him be their teacher, and he wrote something about each child that was special about them, for example he wrote to my daughter "thank you for sharing your Ameilia Bedilia books with our class, you helped make everyone laugh and have a happy day !" and inside each card , he tapped a silver dollar. My daughter to this day , still has that silver dollar and card !