If I'm going to cut out wheat in my diet, what can I eat for lunch?

I'm in high school, and obviously in most public schools there are no microwaves (there was one in my private school which was super convenient). I also don't buy school lunch. I bring my own food (which is rare these days).

I want to cut out wheat in my diet, because it's the main reason why I have a pooch. Basically what that means is I have somewhat of a big gut (Not too big but it's definitely not fit). If I'm going to do this, what food can I eat for lunch when I am at school? I usually have a PB&J sandwich with crackers and water.

FYI, I do not eat beef, pork, shellfish, and most fish (only fish that have gills and fins; nothing more and nothing less).