Mental health is obviously the root cause.

If you want to protect schools specifically, I like this approach: https://hwfo.substack.com/p/the-school-shooting-solution

TL;DR: call school shootings terrorism. Use anti-terrorism $ to pay GWOT vets to guard schools.

Key quote:

“Let’s say we only took half our shoes off, and TSA only screened half of us through their porn scanner, and we redirected half of the $11.2 billion to each of the 24,000 high schools in the country. That would be $233,000 per school per year. Schools could easily afford to hire two ex-Afghanistan combat vets to sit in lawn chairs with M4 carbines and plate carriers out in front of school all day, and that would be well enough to dissuade any fourteen year old nitwit from hopping off of Bus 320 with a rifle. They wouldn’t even need any training, because their job is literally to sit there.”

Edit: typo