<p>I would be upset if teachers used food as a reward for behavior or acheivement on a daily or even weekly basis.
Yes schools do often use classroom pizza parties as motivations for raising the most money for a food bank and the pizza party could also be the theme of the end of the year girl scout celebration, but I think in general the reward or punishment should be related to the goal or misbehavior,if a tangible reward is even needed.</p>