There is no ideal gun control law for this nation. No gun control law will even remotely work. Time has proven this, just like time has proven that enforcement of alcohol laws and drug laws do not effectively work.
Besides, you could ban all firearms tomorrow, and it would be spit in the wind. The removal of all firearms is logistically impossible.
Want to stop or slow down school shootings? Develop a moral framework for the kids because the Left certainly doesn't have one other than do whatever feels good.