From the description of the following video:
Heinrich and Irene Wiens chose to keep their four children from attending a mandatory play and four school days of "sexual education" that taught students an extremely permissive view of sexuality. For this they were fined and then sentenced to more than six weeks in prison for refusing to pay. The father already served his prison term. Both parents contend that the programs oppose their Christian beliefs and that forcing their children's participation is unlawful.