I give my students the financial limits I can go, what the school rules are (written and implied) and then let them choose. They need to have buy-in to make any plan successful.
Subbing! I have been researching but haven't found too many behavior plans. I'd love to hear what people actually implement in their classrooms.
How about an experience vs a trinket? For example, lunch with the teacher or an afterschool science experiment for everyone who meets the criteria.