I taught for several years before moving on to IT actually. I still see absolutely no reason to ban images of firearms. The idea that you can't have a picture of a gun, drawn, worn, or otherwise, just helps to vilify guns in the minds of the next generation.
I cans only shake my head in amazement. Most of these kids see far worse images in 90% of the video games they play. From kids getting suspended for having a mullet to kids getting detention for wearing a t-shirt with images of a gun on it. It's pathetic. I suppose kids can no longer play dodge ball because it teaches violence as well right? Give me a break. It definately interferes and prohibits a persons freedom of expression that's for sure.