I've used that when teaching short "Graphics 101" (not in the first session though) and the math comes out more intuitive than the usual "here's how to calculate a perspective matrix, don't ask where these numbers come from" version.
Students can easily imagine the pyramid from an eye to the window frame, and that it keeps going.
Then I point to an object outside the window and say imagine strings going from the corners of the object to your eye. To do this they would have to go through the window, where do they do that. 3d graphics is finding out where on the window the strings go through so you can stick a picture of thing outside onto the window and it looks exactly the same.
A lot of 3D graphics can be derived pretty easily just from knowing a few basics like divide by depth. I think knowing how to construct a transformation matrix from a coordinate system basis is another one -- that would remove the need to look up how to construct a perspective matrix, for example.
A few things like that will get you pretty far and you can kind of take the same journey of discovery as early 3D pioneers. That's one of the best ways to learn because you're much more likely to remember something you figured out compared to something you just read about.
It gets tricky with perspective-correct textures, but running into issues like that on your own (even if not solved on your own) is part of the fun of learning, I think.