Leaving this as a time capsule in case Alice every wonders what she ate for lunch when she was a kid.
Alice's standard lunch during 2nd grade hasn't changed much from late 1st grade. I make two individual sandwiches using Hawaiian sweet rolls, hard salami, cheese (muenster, american or Swiss), and some mayo. These are 2nd grade Alice's favorite sandwich. Along with that she gets 2 cookies or 2 candies and a small portion of chips.
There is nothing at the cafeteria she much cares for but sometimes she eats there if it makes sense socially (lunch source determines seating opportunities).
Lastly, she is in the habit of sharing her snacks with special friends, that is why there is always two pieces of whatever packed for her. She has just started to mention food trading which I don't discourage, even though its against rules.
Completely Unwarranted Parental Aside: I see this as a Spartan situation, where breaking the rules to make a mutually advantageous trade is the optimal lesson she could learn. She must endure whatever punishment she receives but will get none from me. I just expect good trade and a good reaction to being punished. Those seem like important lessons too. She has ample opportunity to learn how to obey, life is rife with them. Other lessons must be learned - society does not thrive on obedience alone.