DS9 is a big memorizer too. He just listens to a piece and can play it back perfectly. His piano instructor started playing a card game with him called Snap. I'm not sure how it's played, but it's kind of like speed with music notes on the cards. That has really helped him learn to read the notes and he enjoys the game. You could probably do something like Go Fish or Old Maid with music notes on the cards with your DD.
The other thing we do is we let him pick out a piece he wants to learn especially if it's above his level and then we give him a piece we want him to learn. So, right now he's learning the James Bond theme music that he chose and something else the teacher assigned. He enjoys the challenge of learning the harder piece he chose and will then be more compliant playing the "boring" piece the teacher chose at his level.
