Can anyone recommend some fun self-study guitar, music theory and/or piano books for a twelve year old girl? I've started teaching my little sister how to play guitar, but we don't live in the same state, so I want to get her some books so she can continue her studies. I'll be buying her a guitar and she already has a Casio keyboard. I have her started on G - C - D chords on the guitar and the C major scale on the keyboard. I should mention that I've never done any music teaching, so this is new to me. Thanks for any recommendations.