To change or "rewrite" the constitution trying to deal with this subject could dissolve the US.
Banning guns altogether (rather improbable) will only leave law abiding citizens at the mercy of criminals.
More protection in schools could be a starting point to address these awful events.
I'm still in favor of law abiding citizens having a way to defend themselves. My Dad and Mom were almost killed by a burglar with an illegal gun while they were at home!. A burglar got inside my house while my pregnant wife and me were sleeping. If she were to go to the bathroom or anything else, I couldn't possibly imagine what would happen.
For context, it's practically impossible to buy a gun in my country. I wouldn't recommend anyone to vote for laws restricting any law abiding citizen to defend themselves and their loved ones.