gross out kids book -- probably from 80s -- read mid-90s -- barf scene?

THIS IS DRIVING ME CRAZY. I remember reading this book at my friend's house as a kid, but the only scene that stuck in my mind is one in which everyone in a school cafeteria vomits profusely except for the protagonist. He faked puking, too, so no one would suspect him of...poisoning them? I don't know! I think there were also school lunches made out of maggots and beetles. And it's possible that he turned into a wolf at the end, although I could be transposing from another book.

I remember it had one of those campy 80s covers with surprised, all-American looking kids engaged in some kind of pertinent activity.

HELP. (please)

Eat Your Poison, Dear, maybe?

Probably not How to Eat Fried Worms, huh?

They were a series from the 1990s called Barf-O-Rama. I had the first one, and it was so dumb.

http://www.librarything.com/work/5398360