Linklist Educational Games
- "26 Learning Games to change the world". This collection of 26 games cover a wide spectrum, from simple re-skinned known game-machanics to complex simulations and narratively connected collections of mini-games.  (Video on "Darfur is Dying" on youtube: )
- "Oregon Trail", a very common educational game used in US schools during the 90ies. Description in the highly recommendable "TV Tropes Wiki" which also deals with game and educational game tropes (= stereotypes). 
- "Molleindustria - Radical Games". This is an independent game producer who launched classics like the "McDonald's Game" but also controversial ones like "Pedopriest". 
- Ian Bogost, "WatercoolerGames". A blog by game theorist and -designer Ian Bogost, with many examples and entries for serious / persuasive games 
- "Funbrain - The internet's #1 Education Site for K-8 Kids and Teachers". A collection of games to teach math and reading skills.