I think contacting her and telling her that she is a wonderful part of your lives, but now that she is in school and you know how busy she will be, and how expensive things are, her BEST gift to you would be to call, e-mail or whatever communication methods you use, and let you know how her life is going.
If you can get together with her sometime, even better. Tell her that her biggest present to you is for you to be part of her life.
I suspect she will be very happy to hear that because she will have new friends who she will want to buy for and she is at a point where life and demands on your time and money are changing.
HOW THOUGHTFUL of you! Also, tell her what gifts you particularly loved and how you cherish them and her!