As a high school teacher myself, I have a growing conviction that a few legally armed people in every school in the country would go a long way towards preventing tragedies like the ones we've seen.
Not just teachers, but a bunch of other professions may want to consider the idea as well.
The article Glenn just posted here shows that others are thinking similarly.
http://thefiringline.com/forums/showthread.php?t=509009
PS: To the moderators: I hope this post is within the parameters of allowable discussion