How did you deal with the licensing issues? As far as I can see the videos on the Khan Academy channel on YouTube use the standard Youtube license and the terms of service on the Khanacademy.org site states:
Khan Academy grants you, a limited, non-exclusive, non-transferable, non-sublicensable, revocable license to download, install, view and use the Downloadable Content, in object code form, on devices owned or controlled by you, solely for your personal, non-commercial purposes. You agree not to (i) modify or create derivative works of the Downloadable Content …
So technically these resources are not OER. Curious to know how you were able to integrate these resources into your initiative?