Spywatch is a neat game — again from the BBC.  In it, the player has to discover who is the spy working in Great Britain during World War II.

There’s a fair amount of reading involved, though it’s simple language and laid-out well.  Early Intermediate English Language Learners would find it a challenge, but should be able to play it.

There is a lot of explicit language development activity involved.

I’ve placed the link on my World History page under The World in the Twentieth Century.