You could invite them in as a Reading with the Community week. Or I am sure that some of them have some stories they could share about life experiences as part of a Looking at the Past day, or invite them to have lunch as part of a Grandparent/special adult friend luncheon. They could volunteer in the nurses office making calls to kids homes who didn't come in that day, in the library checking in books, things like that.
You could hold a bingo and give a discount for senior citizens...whilst you have them- you could present them with some support options. We have a seniors apartment complex opening near us soon and I'm hoping to get their help with volunteering etc by doing something similar. We'll see...d