The Desert Eagle does a ton of damage per shot, but it doesn’t have very much ammo capacity. I would use an AK 47 with the under folder stock. Plus, the AK has a long barrel so it still does a ton of damage per shot. The best quiet kid weapon is the P90. It has a low profile magazine that gods 50 rounds and it’s bigger than .22 Lr; forget what it’s called though. Anyway, it’s about the size of a desert eagle and it’s held way closer to the operator when in use. It can also fit in almost any backpack. I’m not promoting a school shooting, I’m just listing the best way to arm the stereotypical ‘quiet kid’.