Nervensaegen: Mark Overmars
I used to send Professor Overmars bug reports ages ago for the first few iterations of Game Maker. I got an A in a human anatomy presentation by turning it into a game. Folks had to fly a mini ship in a heart and blast calcium buildup in an inplanted valve. And I used Game Maker to do it.
It's amazing how similar it was back them to what it is today.
And he was super-smart and kind.
As far as classroom games:
Archive.org has The Oregon Trail which is a classic elementary and middle school game that still has something to teach today. Just be careful because there's unfiltered porn in there too.
Tons of sim games - traffic, trains, zoos, skyscrapers, cities, etc.
Neverwinter Nights has been used to build modules to teach setting specific as a multiplayer experience, or to build stories with the toolset and learn some C.
Universe Sandbox to learn about the distances and sizes of stellar bodies and see and play with gravity and mass.
Kerbal Space Program - the very best game to learn about space and gravity and rocketry.