2 Replies
Phil Mayor

If you have a license for royalty free music I am sure there are no issues, music from recording artists would have copyright issues. 

You may be able to argue fair use, but this depends on how much you use, there is a myth that you can use 30 seconds of anyones music under fair use. Not sure of the actual wording but it is more related to the amount used and how substantial that is of the original work.

Also it depends which country you are in.

Some schools are allowed to use works without paying copyright.

It also is dependent on what type of work the music is used in.

Ideally you would seek permission for any work that is used outside of Creative Commons.