What should be done to prevent school shootings!!!

We all know what happened here in florida with this terrible tragedy in parkland and unfortunately this isnt the first time this type of event has happened in the country. With that said its time to really try and prevent this terrible situation from happening again. Let me start by saying this here.....................
I absolutely do not agree with teachers carrying guns in the schools at all!! I dont know about other schools but the highschool i attended many times i have seen teachers almost crossing the line to strangle kids because of their disrespect and lets be honest if you were in the same place you might have that reaction and for that reason alone i feel they should not carry guns because knowing they have that at their disposal might just start new kinds of tragedies, not because I think they have mental issues, but because they just might let their selves go and act in the heat of the moment. What I do hoever feel that should be done is that metal detectors should be in all schools with no exception along with atleast 3-4 police officers trained to fight terror and not run away from it. I know your thinking about gun control and i believe in that myself buuuuttttt, with this president i doubt we can get anything done I mean the guy just wanted to add more guns in the schools smh, but thats another talk I rather not get into, anyways this to me would prevent school shootings to go down, I am not saying what can be done about the countrys problem just the schoools, this is just my honest opinion if you have anything to add it would be cool to put all Ideas and present them to save our kids future and safety, thank you for reading