Ken Trump, a school safety consultant who runs his own firm, agrees that it's a high-risk, high-liability proposal and thinks only a law enforcement officer should carry weapons on campus.
"There's a huge difference between saying, 'I can protect my family and my home,' versus 'I'm prepared to protect the masses,' " he said.
You also have the matter of whether teachers want to carry guns. Nearly three-fourths of teachers said they would not bring a firearm to school even if allowed, a February School Improvement Network survey showed. However, the survey showed most educators believed armed guards would improve safety.
John Benner, president and chief instructor at the Ohio-based Tactical Defense Institute, has trained school resource officers for years. He taught his first class to teachers this spring.
The three-day class sponsored by Buckeye Firearms Association examined mass shootings and taught school personnel how to predict a killer's behavior and shoot on the run amid obstacles like narrow hallways and stairwells. Police officers and SWAT commanders help instruct the course, and participants must have a concealed weapons permit before registering.
Buckeye paid about $1,000 per teacher, which includes tuition, food, board and ammunition. The group will cover tuition and board for the six courses offered this summer.
Benner would like to see all school employees -- teachers, resource officers, administrators -- learn to use firearms.
"I hate the idea of arming teachers, but we have to," Benner said. Signs and locks won't deter an attacker and police can't respond quickly enough, he said. "It's the only thing that's going to work."
Asked if training law enforcement officers to patrol schools was a better idea than arming teachers, Caster, who was the executive director for the National Association of School Resource Officers before joining the Ohio School Board association, said it's not possible.
School resource officers are typically funded by either the school or the local law enforcement agency.
"This is what it boils down to: can you afford to have an officer in every school?" Caster said. "It's not in the budget."
In any event, he said, emotions should not drive the discussion.
"This isn't about guns, it's about a possible tactic," Caster said. "My plea is that we have a rational, logical discussion (about arming teachers) as an additional possible tool."