Shooting at Distance: A Growing Consideration for Concealed Carriers

In light of the recent Florida shootings, there is much talk about arming teaches and having them to carry concealed. I am all for us following the Israeli model where they arm and certify their armed teachers on a periodic bases and have them train regularly. SO what does this have to shooting at distance? If you have a teacher who can hit a "man sized" target at 50 yards, chances are a someone who can engaged targets effectively at shorter distances.