The Music Teachers National Association has put together a list of links that teachers can use to plan for and improve their teaching through COVID-19. This list includes free and paid resources on a variety of topics.
Frances Clark Center for Keyboard Pedagogy has released some free content from their publication, Piano Magazine (formerly Clavier Companion). This website includes webinars, tips, and more on navigating COVID-19 as a music teacher.
The Piano Technicians Guild has useful information on how to care to care for your piano during COVID-19. This includes information on how to best sanitize your piano without damaging it.