The solution is allow concealed carry at schools. That would not cost the tax payer much and would be very effective.
It appears that liberals would prefer more children to be endangered than to do something as unthinkable as actually agree with the bloodthirsty, evil NRA.
The real advantage of the concealed carry option is that until its pulled, no one knows who has one.
Armed guards can be spotted, distracted, eliminated, or just worked around. If the bad guys don't know who has what, planning one of their murderous escapades becomes much more difficult and problematical.
Even schools where no one carries will still benefit.