[smcl]

That was your first programming class? That's actually a pretty amazing idea. I think many people's first exposure to programming is something low-level on the command line (printing like "hello world" then digging around with file I/O, network and other OS stuff) or special-purpose and graphical (making a little square or something in Logo) - doing the graphics stuff with a general-purpose language probably involves pulling in external dependencies or learning a simple image format like ppm/pgm.

Introducing a powerful language like scheme, having a graphical output and planting the idea that students should hunt around for ways to integrate with or otherwise poke at existing applications is smart.