Auo complete field based on info in db

Hi,

Is it possible to have the a field that will auto complete with info from a db?

In this instance i am building a fund raising program for multiple schools.

As part of the checkout process the client wants to have a drop down of the schools. Once the school is selected the buyer would start typing in a students name and the field would auto complete based on the db of students for that particular school.

Thanks,

Brent