Lanza shot deadly 27 people. He must have had weapons able to fire fast lots of rounds. Large magazines and/or mods to those weapons.
Ann is going in this text for more concealed-carry. Many here on TH are for concealed-carry to be law in ALL the schools. That's wrong. Imagine how many 'unfortunate accidents' may happen: spouses/teenagers of teachers getting those guns and going berserk like this guy.