Jim - we get two semesters of firearms repair. We are introduced to the most common guns and how to trouble shoot them. The lessons learned carry over to other firearms. In addition, we are expected to bring in firearms and to service them. Our instructor plays the role of the master gunsmith or customer who expects the firearm to meet industry standard before it leaves the shop. We can replace parts, repair parts, manufacture parts from raw material (I made a hand for a Colt Official Police, a center pin for a Victory Model S&W revolver), make springs, repair stocks and in some cases, refinish the firearm.
For each gun that we are taught about in class, we are expect to disassemble and reassemble them and to take a written test on them (what part does what, if X fails, what are the causes?). Your class grade depends on assembly/disassembly times, test scores and the amount of points earned in servicing firearms.
Last semester I modified three Para-Ordnance 13 round magazines to fit an Izzy polymer frame 1911, repaired a Brown Bess (replica) tumbler so that it would not stop at the half-cock notch, polished the frizzen (it was never polished), refinished a Hawkens replica (after I soldered a rib to the barrel and poured a pewter nosecap), tightened a loose front sight on a S&W revolver, repaired a Browning A-5 that didn't eject (had to make some new parts), repaired a S&W revolver (hammer didn't rotate/trigger locked up - had to make a new part), serviced an Uberti copy of the Colt SAA (clean & lubed it and polished the bushing so the cylinder spun a little better), etc.
A classmate fixed a Trinidad PD's AR-15 rifle that had a canted front sight. It had left the factory that way. Other classmates serviced some 22 rifles for the Boy Scouts. In short, collectively we saw a whole host of firearms being worked on for various reasons. Break open shotguns, single shot rifles, pistols, revolvers, bolt actions (including cracked stocks or stocks that weren't even bedded by the custom maker --- it would have cracked if it had been fired).
By the end of the two semesters of repair, you're supposed to know how to inspect and service a gun. Required (text)books include Numrich Gun Parts Catalog, Brownell's Encyclopedia of Firearms Disassembly, Jack First's catalog (and perhaps a few others which I don't recall). One thing we benefit from are all the videos on YouTube. The classroom has a bunch of NRA Assembly/Disassembly books as well as their Gun Digest counterparts. Students are free to consult with one another too.