It didn't matter that what they had learned was trivial, we all shared and by doing so the rest of us learned something new again. People taking courses go into the experience hoping to get something out of it, but many times don't know what to expect. Many of us don't realize that what we learn or get out of the course is partly in our hands. That first class, we can speak out and make sure that everyone knows why we are there. If the instructor doesn't ask, perhaps you can bring it up.
Interaction is of prime importance in learning.
We learn best while being in a participatory role. We can't just sit there and be spoon-fed information. Make sure you can contact them either via email or phone. You'll have to listen to them unless it is an online course. Tip Two Ask questions.