Khan Academy is like Google Analytics. A great, free service. use it if you want to, don't if you don't. No one's ever forced you to. To the author: If you've g

Khan Academy is like Google Analytics. A great, free service. use it if you want to, don't if you don't. No one's ever forced you to. To the author: If you've got something better, bring it on. Don't try to pull others down.