“What I would really like to see is a curriculum that is sex-positive instead of being all about shame,” Friz said. “It should be out in the open — this is normal, this is part of our bodies and let’s talk about this. It’s an important part of being a human being.”

Some parents also object to the program’s portrayal of girls as more emotional rather than physical, and saying they are more apt to suffer from guilt and low self-esteem after sex.

One of the activities used involves placing a piece of tape on the arm of several students until it loses its ability to stick, to demonstrate that you could lose the ability to bond with a spouse.

Another activity to demonstrate the effects of having had sex with more than one person involves chewing cheese crackers and spitting them into a cup of water, which is then poured into another student’s cup. All the while, one student’s cup of water remains pure.

Nathan Zipoy, 40, who has a seventh-grader and ninth-grader in the Francis Howell district, said he doesn’t want his daughters to feel like “damaged goods” if they choose to have sex before they get married.