I think Kerbal Space Program might be educational. It felt educational. Obviously, it was not perfectly so. I'm almost positive that, in real life, if your booster rocket fails to clear your flight-path at 14 thousand meters and winds up running into your liquid-fuel rocket, sending your spacecraft into an out-of-control spin, that's basically certain death, and not something you can overcome by cutting your engines and making adjustments with your maneuvering thrusters until you regain control. But aside from the concessions made to the fact that, in unskilled hands, ninety-nine out of a hundred rocket scenarios end in fiery death and thus would be unsatisfying to play as a simulation, I think I was getting some pretty good information about the effects of retrograde acceleration, conservation of angular momentum, the nature of gravity, etc.
I don't want to overstate it, of course, but the the feeling of having learned something is a good feeling. I'm trying to think of other games that have been similarly enriching, and I'm coming up short. Maybe the Civilization series, if I ever bothered to read the civopedia entries (although at that point, why am I not just reading a book?) Possibly Ship Simulator Extremes or Never Alone, although in both those cases, the educational elements mostly came from unlockable video extras.
Kerbal Space Program is notable because its educational properties come about in the gameplay itself. It would have been better if I'd read a science book beside it, so that I could have some hard numbers to go along with the visualizations (or, more accurately, when I studied this stuff in college, it would have been useful to have some visualizations to go along with the numbers), but even so, on its own, it was neat to see the relationship between acceleration, inertia, and gravity.
It also helps that Kerbal Space Program is a fun game on its own. Building up a new model of spaceship was super-easy, in a purely practical sense, so there was very little delay between my most recent horrifying disaster and a new, slightly-modified prototype that would theoretically prevent it (but often didn't). Similarly, flying your ship with its realistic physics and overly-sensitive controls was often satisfying on its own.
I ended my game on a pretty high note. I'd finally got to Mun and back, and then all my science experiments burned up on re-entry, so I redesigned my ship and did it again after only two or three failed attempts. Then I had about a half-hour left, so I messed around trying to complete contract assignments in the hopes of squeezing out some better automation technology. It was immensely satisfying to overcome what seemed to be an impossible technical challenge. I never actually landed on Mun, or got any probes outside my home planet's orbit, but I figure it's only a matter of time.
I'm definitely going to play Kerbal Space Program again. There's still so much of the Kerbol system to explore, and from what I understand, there are mods that make the experience even more hard-core educational. I look forward to an endless series of ill-thought-out, improvised rockets exploding in ever more convoluted ways.