Don't you just love how one is not supposed to make comments because it might offend others? Don't say anything patriotic because some in the class may not like America. Don't pray because maybe there is an antheist who will be offended (100 Christians - 1 atheist - atheist wins), don't say the word gun because someone may be offended - I could go on and on - what ever happened to our rights? Don't want to sidetrack the thread, but our gun rights are slowly being taken away from us, and it's starting in the schools when they're young and impressionable. They carry those teachings on throughout their life. The 2nd ammendment is clear - yet we have to fight everyday for our rights when our founding fathers knew all too well what would happen when a government became too strong. They weren't afraid of guns - they were afraid of government.
I commend you on the handling of the situation at school and wish you well in all your future endeavors. It sounds like your doing an excellent job of teaching your boy responsibility.