These "My Ideal America" posts aren't really "ideals" because, for example, ideally no one would ever need a gun for self-defense. These are really just musings about what I think is technically possible but actually extremely unlikely. They're just daydreams.
So in my ideal America, schoolteachers (and anyone who works with kids, really) would want to and be permitted to have concealed weapons. It would be considered a form of professional development--like first aid and CPR training--to better prepare you to protect the children you watch over. You wouldn't have to do it (I usually have an aversion to new laws forbidding or requiring things); it would just be something many people do, and something that shows your commitment to doing your job well.
And in order to have a concealed weapon around children, you would first undergo extensive background checks and training, moreso than what is currently required for a concealed carry in some places. You'd be very comfortable and familiar with your weapon. Then perhaps I'd feel the same way at an elementary school that I do at the shooting range: safe.