Learning how to read the notes on the stave can be a slow and difficult process for youngsters (and adults!), and this app takes a fun and simple, arcade game style approach to the subject. You can choose from Treble, Bass and Alto Clefs and customise the range of notes to include or exclude ledger lines. Notes fly across the stave on the screen and you have to guess the correct note. A spaceship fires at the stave, akin to Space Invaders. The speed of the travelling notes increases with each new level. 

I have used this app with lots of children in a private lesson context,  but it works even better in a school situation. With a lot of pupils you can create a class leaderboard and encourage some healthy competition between classmates!

Download Staff Wars here

Also see Note Perfect which is another note-recognition game.

I'm going to be recommending a different app every week which I've found helpful in my life as an instrumental teacher, producer and/or musician in general.