Context: the permission slip does not give you any indication as to what will be taught/said during the course. You have called the school and they claimed they did not have anyone at hand who knew the material that you could talk to. You may or may not be of the same denomination, but are aware that other children who will be attending may not have the same faith as you/your child, if any. They plan to load children by bus to this church you've never been to with only church members and school staff monitoring the kids. This will be a 12-2:30 long event. No further sex. ed. will be given during that semester to that grade of students (6th).