Why can't our military protect OUR children??

With everyone crying out about putting armed guards in our schools to protect our children and the prospect of having most of our troops coming home over the next 4 years, why can't the government restructure the military to include posts to protect our children while they are at school?
It is only a 5 day a week job, with summers off. Most schools have 1/2 days and teacher planning days every week so tech it would average out to about 4 days a week work. They get the same holidays off. And I'm sure the military parents would love a chance to protect their own children instead of the children on foreign soil.