I'm not sure how I feel about educational video games. I mean they sound like a great idea but so does low alcohol beer and look how that turned out....
Anyway, I haven't even downloaded this let alone played around with it but 'Immune Attack' does look interesting if you a) are interested in the human immune system or b) loved the movie 'Fantastic Voyage' where a spaceship is shrunk to microscopic size and injected into someone's bloodstream. There's also an episode of Futurama like that, a tribute to the movie I guess, but I now realize I have the two confused in my mind.
Anyway, in Immune attack:
You must navigate a nanobot through a 3D environment of blood vessels and connective tissue in an attempt to save an ailing patient by retraining her non-functional immune cells. Along the way, you will learn about the biological processes that enable macrophages and neutrophils – white blood cells – to detect and fight infections.