We have several keys to our approach to curing core educational needs. First, if you make a game entertaining enough, kids will find a way to play it. In practice, that means that we keep pushing the gameplay and technology in our games until we get to the level of "Real" video games.
Second, we absolutely have to make the game spectacularly effective, with built-in assement, so that children always walk away with total mastery. That means finding the very best pedagogy in the world, and then improving on it by capitalizing on the limitless possibilities that artificial intelligence and virtual worlds can offer.
Finally, give it away. We absolutely provide substantial value for folks who can afford to upgrade, but give away the core education to the folks can't. We call it the Robin Hood business model and it seems to make everyone feel really good about the whole process.