iOS These people are charging for Stanford classes.

I found this site from a search and they have the Stanford free iTunesU on there and they are charging for it.

https://www.coursehero.com/file/p37...nstance-variable-But-we-only-access-instance/

How can they do this?

I'm a huge fan of these online schools because if they are done right, people can get a free/cheap education and that's very important. It's sad to see that some are abusing the system.