You may need to contact Adobe Tech Support for your specific needs.
Is Premiere Elements installed on your network or on the C drives of each computer? The program must be installed on the C drive in order to work properly. You can't run the program from a network installation, and that could explain why you're having the problems you're having.
If you've got Premiere Elements installed on your C drive, you should be able to access your video files if they're stored on the network. But this depends on how your network is set up. It may not be possible for all of your students to access material out on your network drive and remain connected to it the same way every time you open your project.
In other words, you're using the program in ways it's not designed to be used. This is why you may need to contact Tech Suport and see if they can recommend a solution, short of each student having their own complete installation on each computer.
Thanks for your help. I'll talk to the IT support at school and see what they say!
I'm not sure your IT people will be able to help you, Joan. At least not unless they'll let you install the program and your work materials on the individual PCs rather than on the network.
The bigger issue is how Premiere Elements performs on a network. And that's something only Adobe fully understands.