We would check the server and make sure that GS/OS has been properly
installed--with the Installer--and that all the necessary files are there.
After you verify that, take a look at each Apple IIGS computer.
If the problems show up on all systems in this network, take one of them to
another network and see if it starts properly there. Also, check to see
what is happening before the network fails. Maybe a student is trashing
some crucial files within the server folder or within the GS/OS system
folder on the server.