To positive,
While I agree- there is too much nosh and prizes and whatnot in our schools, still some of the time it’s a good idea. The Rambam says you should reward children for learning. I don’t think this has to be overdone. Also, for problematic kids, the shrinks have something called token economics. This method is to reinforce good behavior. So there are good reasons to do this, but like I said before if it’s overdone then it defeats its’ purpose.