Music selection is a collaborative process.
1. Some pieces selected by the teacher are pedagogically geared to develop certain skill sets and can be the foundation upon which other pieces will be more easily learned.
2. Some pieces can be fun, flashy or dramatic sounding while being easy to moderately hard, and are taught using the various technical skills you've already developed.
3. Other pieces may appear to be quite hard - although it is certainly within your reach if it is assigned to you. Such pieces are broken down into small achievable steps and are incredibly rewarding when completed.
Having a varied repertoire is such a great part of enjoying music that you can successfully and easily play while learning pieces that bring you to another level of expertise. The nuance of repertoire selection is a delicate and major part of developing students who feel love and accomplishment for their musical achievements while feeling inspired to learn even more.
Jodi Russell, B.M.,M.M.,NCTM