if you're talking about a legitimate school, then it needs to have a ".edu" address at the end of the web address.
i THINK i read a while back that there are only a couple schools(community colleges) in the whole country that have a gunsmithing program. Everyone else learns the hard way, or through an apprenticeship(which is probably also the hardway)
I have built probally around 40 guns for myself and other individuals, including a few mg's and suppressors for a local mfg/sot. In my opinion i would go to a local college or get into a training program for machine work. Some are free/ low cost. That will get you the basics and then some for metalwork and you are then 1/3rd of the way there for bieng a gunsmith. You can join a place simmilar to this also this place is the best to learn FYI.