Looking for an advice – using PC games as a way to teach English

Any Infinity Engine game.

Point and click adventures, with some hand holding since they can be a little obtuse occasionally. Voice in one language, subtitles in another. Lots of repetition, no reason to rush through it.

I used to play games to learn english as a kid. There's a fishing game where words are written in the fishes and you type those words to fish them. There's also the reader rabbit series. I don't know if they are still available today.

Just to give you guys a small update.
I have been so far able to get a few keys for my school:
20x Metamorphabet
8x Crayon Physics Deluxe
1x Hidden Folks
1x Monster Prom

Since we had Christmas lessons I was able to do 2 full lessons with 5th graders (10-11 year olds) and they totally loved it :) The only bad thing is that Cryon Physics Deluxe keeps decalibrating our interactive white board for some unknown reason :-D

I have also taken a lot of your suggestions into account and I have emailed the devs if they would like to participate in the experiement :) Sadly majority of them didn't respond (and ubisoft just declined :-D )

That's a great idea! Wish you all the luck!
I was born in Brazil and basically that was how I learned english (at least what I know :p).
Yeah, we also study it at school, but 95% of what I learnt came from Games, Movies and TV Shows.
Since I didn't have Steam at my early age, got what I have now from playing Pokémon, Mario, Zelda and other things on the Gameboy and Gamecube :p

Great to hear you've been able to get keys and use some games in class.
I don't have any suggestions that haven't been written already, but good luck finding more!