Guns already allowed in schools with little restriction in many states

"More than a third of the states already allow teachers and other adults to carry guns to school. In most cases, all you need is the equivalent of a note from the principal -- you usually don't even need law enforcement approval. ... The real debate is over proposals to create exemptions from gun bans in states that don't have them. Such measures have been introduced or proposed in Alaska, Florida, Indiana, Maine, Minnesota, Missouri, Nevada, Oklahoma, Pennsylvania, South Carolina, South Dakota and Tennessee."

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