A John McGregor teacher has taken his quirky teaching style to iTunes.
Last year Jon Orr was approached by Apple to create a "Principles of Mathematics" course for its online education database.
Orr says creating a virtual classroom similar to his own was important.
"I first didn't want to, because I just didn't think it would match what I really wanted to do," he says. "With the use of Twitter and social media and sharing that kind of sparked the collaborative part and created that part of the course."
The course now has over 6,600 users from across the globe.