I need help packing food for my field trip?!?

On Monday our class is going on a 5 hour field trip up Mackinac (mac-i-naw) Island (were staying for two days :D) and were only stopping twice on the way up, to the Claire Rest Station or something like that, and to a little park to eat our lunch. I'm figuring I'll get really hungry, so 'm going to pack some snacks. I don't have a cooler or a lunch pail soooo yeaahhhh.......I was thinking something small like poptarts or an apple (i don't really care if its junkfood i love everything!) thx!!! :D