The theme in my classroom is ladybugs (I'm a collector). I keep a bag of small pre-printed tickets hand called "Bug Bucks". When a student is caught doing something positive in the classroom, he/she receives a "Bug Buck". The students place their bucks in a plastic container they keep inside their desks. When a child has collected 10 bucks, they cash them in for a trip to the class treasure box. I also take "Bug Bucks" as well. Students may have to give the teacher a buck for excessive talking, misconduct, etc. This "buck" idea can be adapted to fit the theme in any classroom. In our first grade pod we have everything from "Bear Bucks" to "Cow Cash". This has been a very effective way of rewarding positive behavior in my class!