Curiosity, about the pedals, about how a piano makes sound, about music books around my studio...talking with my students and answering their questions is a simple yet very broad way to foster their love of music. Listening to students' questions and sharing my own thoughts and opinions has a profound impact on them. I know when I look back on my lessons with teachers I remember a lot about their personalities and interactions with me and how their love of a subject helped to develop my own respect and joy on the subject they were teaching.
A great example of a teaching moment I observed was watching my son's first tennis lesson at age 5. The student before him was cleaning the balls off the court at the end of his lesson with a tennis ball vacuum, and my son began following him around the court trying to figure out how this contraption worked. The first 20 minutes of his first tennis lesson were spent lying down on his stomach with his coach pushing the vaccum back and forth so that my son could figure this out! Students have so much to learn... sometimes it's not about teaching them to hit the ball, or play a scale, sometimes it's just about getting their interest.