I would recommend talking about things in "student centered" terms. Its more about the experience of music than the actual performance. But I think it is very important to show the interviewer how you can collaborate with the "real teachers." There are plenty of things you can do to tie in syllables for language arts, numbers/counting/fractions for math, songs to tie in with events for social studies.
I'll tell you I am glad I did it, but at times it was lonely. Elementary teachers really stick to their groups and sometimes you are on your own (or always thrown in with PE). Once the other teachers saw I was really teaching, I maintained discipline, so their kids didnt go back to class wild, and I was willing to incorporate things from their classroom, they loved me and it definitely made me feel like part of the team. Good luck.