And you hit that nail directly on the head. Back in the late 90s, I was in jr high. And it was the same way. we had a lab full of these, the 5200/75. They had At Ease, and was used to do exactly that. I used to piss the computer lab teacher off because I would hack At Ease and drop into finder, he could never figure it out. Only way I stopped was the threat of suspension. He was running At Ease 2.0 i believe. Hell i cant remember how I did it, but I loaded finder through the debug prompt. The bad thing about it was the fact it only worked one out of 5 times due to System Error, Address Error bombs.
However with a twist, there was a workgroup server and everything was wired via coaxnet, because the program called CCC which is a math lab program, used the server to store user database information. So, CCC required an appletalk share to be mounted before it would run.