Yes, thanks for posting, George! This is very cool.
I haven’t yet played Portal 2, but Portal 1 stood out to me as a strikingly clear example of how learning principles are embedded in game design. After beating the game, you can play it back with “commentary,” which turned out to include almost nothing about the story and instead a ton about the pedagogical and rhetorical choices intended by the sequence of levels and corridors (i.e. what is revealed when; what you have to see before you see something else), down to the shapes and colors of tiles and the placement of lights and loudspeakers. So this Teach with Portals initiative could be an excellent opportunity for conversation between teachers and designers, if nothing else.
FWIW, they seem to have seeded the “lessons” page with examples from math and physics, but there are tabs set up in anticipation of Chemistry, Game Design, Language Arts, and Other.