It can be used to teach history, folklore, mythology, even religion.
Oh boy here comes the 70's/80's again!
Character Generation:
No, teach people to make a character, not generate the results of the character mechanics into a character sheet. You might as well be trying to teach them game design.
Kid: Why does this race get this when this one doesn't?
Teach them to make an idea for a character, then tell them some things that might fit, even if just limiting to race and class.
Like I would expect a kid to do as being explained half of this stuff, I glazed over at the rest of the article.
I'm sorry, I just don't agree teaching 4th edition is a way to start, especially not with all the stuff to try to memorize and think about.
Still the best way I have used to teach ANYONE D&D and its teamwork and other aspects for the most part, is start them trying to read no books on it, but talk with them about designing a character. Someone like Conan/Kull, Merlin, etc....get them into understanding the game is just there to help you make those things.
After they have a good idea what types of things they can come up with, then let them start working with the rules of the game. By then they should have played a few simple games to get the idea of how people play together and working as a group, etc.
Otherwise all that "other stuff" being taught as skills, is often shadowed by the game rules being taught if the foundation is in the game rules itself.
Do NOT use D&D to teach religion. This is between a "younger gamer" and his/her family to discuss, same as you wouldn't try to teach them about sex.
Change clerics if you need to where religion and gods isn't a part of the game, but leave some things for parents to take responsibility for as it is there's not everyone else's. Especially since you are dealing with 7-11 year olds, and you can only risk causing problems for them at home if you push a subject parents may not be ready to talk about with their kids.