They could sing a specially made up song, and give her a recording and framed copy of the lyrics.

You could have the kids put their hand prints on porch pots in shapes of hearts and add flowers to it-- Add a saying that reads "You're Always in our Hearts"-- this way she'll always have something to remember the kids by.

As a principal, I like the idea of the song. In November, I was going to be promoted but I turned it down. Since then, each time we have a program I have the opportunity to hear another song the children learned that they were going to sing to me. I am so glad I didn't accept the promotion, but it also made me know how much I am loved and appreciated by children, parents and teachers.

You could have dinner in her honor and then have a short program where children perform and give the principal an opportunity to address the audience. Parents prepare the dinner so everyone is included. It becomes a family night.