> 30 kids in a class is still insane.

It's also what happens when you can only hire that many teachers.

> The top level kids can be ignored as not-a-problem(giving up the chance to make little einsteins). The mid tier kids dont get the help they need to elevate; and so teachers are burnt out attempting to make failing kids try to pass. Everyone is lost.

I've been there, teaching programming at a decent university, and it's basically triage. The top students will indeed take care of themselves, and the bottom ones are beyond help. Your job is to encourage the top when you can, but mostly to teach the middle, and help those at risk of falling into the bottom. It's grim, but it's the best you can do.