Using banks, airports and courthouses as examples of the use of armed guards does not fit into a school atmosphere. I have observed most schools are fenced, having a main entrance.
Instead of hiring armed guards, almost all cities have a great resource of guards available — off-duty police. Stop the problem before it enters the school grounds. The school district could employ a uniformed off-duty policeman at the one and only entrance to the school.
The benefits of using off-duty police are immense. They are trained, they would be part-time, and benefits would not be required, other than, say, workers' compensation. Generally speaking, the children like the police.
Certainly one entrance is inconvenient; however, in the world of today, all must put up with some inconvenience in order to ensure safety.
If the president and the rest of the politicians want to do something instead of a bunch of tough talk that accomplishes nothing, perhaps government funds could be available to school districts to assist securing school sites by paying for the part-time, off-duty policemen.
This is just a suggestion. I am sure there are a multitude of alternatives and ideas that could accomplish the end goal: safety for our schools.
Tough talk from Obama will not get it.