The idea was not original to us. The material was not original to us. But we had non-Christian families saying they might be willing to come to a parenting course, so it seemed good to us to try one.
So, fresh from our experience, here are some suggestions on the things to think through for a parenting course in your own context.
Purpose
Work out whether the course is going to be primarily aimed at bringing non-Christians in and establishing links, or to equip church members to be better parents. The two are not mutually exclusive, but the content of what is said, and the assumptions that you can make are, of course, very different.