As far as the research and your feeling of being presumptious in teaching them, you might present it as situation in which you're teaching each other. That is, as you share with them the "joys" of internet research, maybe they can share with you and their classmates the kinds of non-internet research activities they do. Have them keep working bibliographies (or you can call them research notebooks, if that term seems less formal) and talk about surprising things they've learned or sources that made them rethink their opinions.

Sounds like a great thing to do, and I'm betting you'll enjoy it immensely. St. Augustine said, late in life, "I am still learning." Other than "I am still cycling," I can't think of a better motto for one's later years--in fact, one's whole life.

Here's a term for older students that I've heard: SOTA (Students Over Traditional Age).