Good lunch for a cl trip.?

I'm going to Trenton on a one day field trip. I don't like sandwich's, Lunchables, or anything like that. I don't want it to be too big or to small. The real trick is getting something that i can easily dispose of after i'm done eating that isn't to non-filling. It also cannot be too messy such as salsa in a container. If you have any ideas that would be great thank you.