Is there anything you're not allowed to bring to school? Our school division has banned peanuts/tree nuts and a couple of other things.
We found pea-butter at a local healthfood store that Beemer likes, so we do sandwiches like that.
Other than that, fruit, yogurt and a small treat (like 5g CHO of something) are staples. My wife makes homemade granola squares and fruit leather for him as well.
I'm not on any kind of carb limit, but I like to make sure that I have a couple different kinds of fruit available throughout the week at work. We do bananas, apples, cantelope, oranges, watermelon (in season) and honeydew.
There's a snack here in Canada that you may have as well called Sezme Snaps (come in honey or vanilla flavoured) that are about the same carbs as graham crackers.
Also...some of the carb-regular stuff becomes more tolerable if you mix it up with some free carbs like carrots, different flavours of cheeses, etc.
If you have a thermos you could also do a fruit smoothie!
Hope this helps some!