Ideas for a teacher retirement party and music?

it's the last art club meeting but it is also our art teacher's "surprise" party for her retirement. what are some fun activities that we can do and songs that I can put on a cd? i want bittersweet inspirational songs or feel good songs. something to set the mood but not put a downer on the party? I have no idea what to do as far as activities go. I was thinking decorating cookies but that doesnt seem enough. my teacher likes giraffes, teaches drawing and painting, she's a little crazy, and she's retiring. what songs would be perfect for this occasion?