Here are some apps recommended by our faculty:
Finale Notepad – use to put notes on printed page. Free version can get your pretty far.
finalemusic.com
Note Flight – use to create and play back music.
noteflight.com
Flashnote Derby – made for children to facilitate note reading.
flashnotederby.com
Musictheory.net – for more advanced music theory learning.
musictheory.net