PIEDMONT, Calif. — Phones were ringing off the hook at school district offices Monday as word spread about Piedmont High School’s fantasy sex league involving boys in varsity sports and girls who participate in sexual activity, then rack up “points” similar to fantasy sports leagues.

The media coverage exploded over the weekend with reports on television and online postings after the school’s principal, Rich Kitchens, issued an advisory to parents and news outlets that the league came to light after a recent date-rape assembly.

Kitchens acknowledged the practice might have existed for several years and involved alcohol and/or pressure by older students to participate in the league through peer pressure.

“The advisory was a no-brainer,” Kitchens said Monday. “It was important to share with parents what we knew. We tend to take a broad view of the well-being of our students. It’s not just about reading and math.”

Kitchens said school officials’ investigation and talks with students “convinced us we may not know everything, but we know enough, that kids were hurt.”

“Good kids can make bad decisions. We all make mistakes. The key is what you do afterward,” Kitchens said.

He said he had no sense at this point how many students were involved in the “league.”

At an assembly planned in early December, students will be confidentially interviewed one by one afterward, Kitchens said, not only about this issue but others such as cyber bullying or harassment.

Response from parents has been mostly positive, he said.

Schools Superintendent Connie Hubbard issued a statement Monday that said, “This is a matter of school and family working together to support our teens to make good choices and to treat each other with respect and dignity.”

Interim Police Chief Scott Wyatt said Monday there have been no reports of sexual assaults in the wake of the scandal.