It depends on what materials you use in your classes.

Copyright protection grants a copyright owner of a work the exclusive right to prohibit others from using that work. This means that, if you want to use another person’s copyright-protected works (e.g., teaching from sheet music or playing recorded music), you need to obtain the right to do to. You can either obtain permission directly from the copyright owner, or obtain a licence from the relevant collective management organisation (“CMO”) managing the relevant rights in those works. A CMO is a private entity appointed by copyright owners to manage the licensing of their copyright in a collective manner for efficiency both for copyright owners and users.

However, if you use only public domain works in your classes, you do not need to obtain permission or a licence. You may use public domain works freely. These are works in which copyright has expired (e.g., the copyright in musical works expires 70 years after the death of their authors). This would include sheet music written by composers who have died more than 70 years ago.

Even where a particular work has entered the public domain, there can still be copyright protection over sound recordings of that work being performed. In such a situation, the musical work itself may be in the public domain and free to use (e.g., the sheet music) but the specific sound recording of a particular musician performing that work may still be copyright-protected (i.e., you would need to obtain permission or a licence to play that specific sound recording in your class).

You may refer to the Copyright Infopack for more details on the above.

What is the difference between sound recordings and musical works?

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