I was a big fan of shelf-stable snacks in college. I usually had 6-8 solid hours of class time (art studio), so I had to be able to eat while I worked. I usually had at least one, sometimes 2 or 3 of these ready in my bag:
- Cheese & crackers. Either cubed cheese, or those individual spreadable-wedge things. But be careful of the garlic/chive flavored ones if you're gonna be social!
- Veggies & dip. Hummus, cream cheese, ranch dressing. Switch it up.
- Sandwiches. Which I know can get boring, so you need to change it up. I liked cream cheese & cucumber, or nutella & banana. And if you need to use up some lunch meat but just can't stand another turkey sandwich, slice it up over a green salad.
- Pasta salads. Really any kind of salad, as long as you don't use mayonnaise in the dressing. I like tortellini with pesto & grape tomatoes.
- Jerky, string cheese, & fruit leather. If you take the time to search the "lunch box" aisle at the store, you can find less traditional, more 'grown-up' packable things.
An ice pack and an insulated lunch bag should keep things cold for a good long while, unless you're leaving your lunch in a hot car all day.