most likely because there are a few differences between project and challenge based learning models

then it would not be something they have created and could get credit for.

probably the same reason they insist on using file formats that make using your OWN music elsewhere almost impossible!

it's like iTunes or bust!

the "challenge" refers to the students forming the big idea, essential questions, and possible solution --instead of the teacher

so, tell me more about Apple's challenged-based. Is there a website?

more info at: ali.apple.com/cbl/

what I have seen I really like - will have to read and take a closer look