bugsiee Oh man, I can totally relate to difficult schedules.
For coming home super late, I wouldn't recommend having a full blown dinner at 11:30PM. If you get a chance to have a snack before (bread with cheese and vegetables or vegetables with hummus, a hard boiled egg, something that's filling and will get you through your class), eat a little fruit or a bowl of cereal when you get home. I remember working for my part-time job until 11PM and getting home and eating the entire world. It made me feel really bloated and heavy and I had trouble going to sleep because I was still digesting.
For lunch ideas, I always take vegetarian options so that they don't spoil. If you have access to a fridge and a microwave, take whatever you usually eat. I tend to go for salads with veggies and hard boiled egg or a veggie sandwich (hearty multigrain bread, hummus, grilled tofu, tomatoes, cheese, cucumbers and a side of some kind of veggie, usually carrots).
If you absolutely need a snack, I personnally try to have nuts and dried fruits on hand (try to get unsalted and unsweetened). If you absolutely need a bar, my favourite kind is Larabars, they are super clean and fill you up like crazy!
Think protein when you're packing things for school, it's usually what gets me through the day!
Oh, and have a good breakfast, it helps!
Don't hesitate to PM me if you need to talk