If this is what it seems, that policy will put kids in the hospital. Not good.

I only see the BoingBoing summary and the video link, so I'm not sure whether there is a readable version of the original.

http://www.boingboing.net/2011/05/02/school-principal-ban.html

When I was just starting school I had allergies to wheat, dairy, eggs, and red meat, among other things. I was never able to eat one of the cafeteria lunches without throwing up. It was quite a mess to clean up.

From what I've read about the story, I think this policy is dangerous, and I suspect it violates the Some Americans With Disabilities Act too.