The GIMP and thin clients

We just started offering a digital media class at our school this year. Currently, the students are using the GIMP, an outstanding free program with a fair amount of Photoshop functionality. It's not a full-blown replacement for the industry standard, but it certainly works well for our purposes. As usual, free is good. Unfortunately, the only place it can consistently be used by the entire class is one of our Windows Terminal Server labs.

While performance is acceptable, users in other labs attached to the terminal server reported performance problems while students in the digital media class all fired up the GIMP. As more students loaded up and began manipulating images, performance continued to suffer across the board. Obviously, thin clients aren't designed for multimedia applications, but I was hopeful we could make this work acceptably for the single class.

The question then, is how does the GIMP work in larger Edubuntu labs and is there a way to make this work cheaply and efficiently? Share your experiences with the GIMP, terminal services, LTSP, etc. The goal, of course, is to make this sort of software as widely available as possible, as cheaply as possible, without hurting productivity and web access for other users.