In addition to writing software for clients, I write some free software.
DBSchools Music Gradebook
Music Gradebook helps music teachers and their aides assess music students on their instruments and record and report on their progress through a book or series of books.
Starting with the 2015–16 school year, Stanley Middle School (where I volunteer in the music department) uses block scheduling. Period Clock is a webapp that, during the school day, shows which period we are in, and how much time remains, as well as an accurate graphical display of the time periods.
Here is the music department’s period clock.
These next two produce sounds, so please check your volume level before proceeding.