Introduce real food back into the lunch program.
In the 70s, we had real food made by farm mamas. No one could concentrate in the class before lunch time. Oooh, lemon pepper chicken with real chicken pieces and made from scratch hot yeast rolls could be smelled all over the building. Every tray every day had some version of peanut butter - a pb cookie from scratch, apple with pb, those heavenly yeast rolls with pb and honey. And no one died.
LOL, I always think of the classic “Mr. Bungle” video, and how huge a piece of chocolate cake they got in the Cafeteria.
https://www.youtube.com/watch?v=2XGG1NouAzg