I agree that students need to actively be involved in choosing pieces. It is difficult to find the balance between foundational work and work they want to do, though. Both are necessary. It is also difficult to get some kids to speak up and say what they want to play or to even know where to start with finding pieces. They don't have the experience to know what they want p[retty often. I try to offer lots of different pieces, once they get to 1st grade standard - and I try to find pieces that I think each one will like. There is such a huge difference in progress when they play things they enjoy - but I don't always succeed. This last term I have had a few students seem pretty unmotivated, and I have found out towards the end of term that being busy was an excuse for not speaking up and saying they weren't really into the pieces they were learning.
I think my case is one that shows a certain freedom is necessary to keep interest going. When I look back, especially now as a teacher who comes across attitudes like my own was, I realise how patient my teacher was. I rarely did the technical or structured practice I should have doen to be a very good pianist. However, I loved music. I played everthing I could get my hands on - but not with good skill and interpretation. Nevertheless, my teacher put up with me - I bet she pulled her hair out at times thinking I was wasting potential. But, my love of music was never set aside for some agenda. I have played many pieces and never forsaken music whenever I have had the chance to have it in my life.
Annah