Chicken soup with square crackers (aka saltines), 6 tater tots, and a Pluto (no, pluot! DYAC)
I even drew an arrow on the thermos to help A know which way to turn and open. I thought that was pretty clever.
Verdict: Bust! For snack, I sent a container of grapes, and stuck in the remainder of his breakfast, probably about a third of a whole wheat cinnamon roll with sunbutter. I guess he ate all of that at 11:00 for snack so when lunch rolled around and 12:30, he wasn't all that hungry. The soup was virtually untouched, the crackers had been added to the soup for a lovely congealed mess, but the tater tots were gone as well as half of the pluot. Tragically, A did not close his thermos all the way so it leaked out all over his lunchbox and into his backpack. Ugh.
So now I'm rethinking, maybe it is good to send a hearty snack and a lighter lunch. I'll have to think about that.