Acidulate the apples. Leave the banana alone.

Apples stop browning when you dip them in acidulated water, but bananas basically do what they want and you should just pack them whole.

For apples, the enemy is oxygen reacting with an enzyme. Lemon juice works, but it can leave a citrus taste kids notice. The cleaner trick is a saltwater bath: half a teaspoon of salt per cup of water, soak the slices for a couple minutes, then rinse. Kills the enzyme, zero salty taste, stays crisp for hours. Honey water and vitamin C powder work too if you have them around.

There’s also the rubber band hack: slice the apple, reassemble it, hold it together with a rubber band, pack it. It stays white for a surprisingly long time because there’s barely any exposed surface. My neighbor swears by it.

Bananas are a different story. They don’t brown from oxygen — they brown from bruising and their own ethylene gas. So citrus juice tastes weird and barely helps. Just keep the banana whole and peel it at lunch. A hard lunchbox or a banana-shaped case prevents the bruises that turn it brown by noon.

Your kid would rather eat a whole banana than a weird citrus-soaked one anyway.