Two of the possible reasons that schools in Switzerland might have adopted the sex indoctrination program (story linked above) are given below.
1) Swiss lefties have so lost cerebral cortical activity that they believe their offspring have to be taught how to play with themselves.
2) Swiss leftists feel more comfortable having sex with young children, and wish to formally prepare the kids for the interactions in kindergarten.
Click that link if you have a strong stomach, and see if you can come up with more possible motivations for this toxic weirdness.