Make sure you have the same wads and scripts that are being used for the students, on your machine. That way, all you have to do is copy the WMP file.

The other problem you WILL have, is that the standard version has many less features than the commercial edition has. Here, you can do two things:

1) Update your standard version to commercial edition.

2) Make sure your students don't use features not available in the standard edition. EX: colored lights; mirror effect on bocks; etc... Most of these (like the ones mentioned), will not create error messages, but simple wont work. ex: colored lights will be monochrome, mirrored surfaces will not be mirrored.

I would go with step 1, but it depends on your budget, and how long the class will last. If it's a one time class, then I'd just do standard. But if this is going to go on for over a year, then you really should *upgrade to the commercial edition.