Don’t be to hard on yourself and try reading the material, then watching some videos on the subject (things like smarter everyday touches a lot of the topics or Khan academy) and then give it your best shot. Every time they have a question you don’t know, find some material and learn it with your child. Teaching them how to research is a far more valuable skill for life for them then getting the answer immediately from an expert.

More simply put, your child will appreciate the time spent with you and the skills learned far more than a quick answer.