Nice try, but you're actually going to have to attend classes in person if you want an ED visa. Also, they're cracking down on ED visas now (rightfully so). Not as easy to get anymore.
What else do you need? The directions are right here. Good luck lol. You need a letter of acceptance from an employer, among other letters. They are listed here:
I would ask the embassy or an immigration official about this. There might be inclusions for special needs but the general rule is 20 years old which it appears that you're aware of. Beste wense.