SAN FRANCISCO (AP) — San Francisco is suing its own public school district to try to force classrooms to reopen amid the coronavirus pandemic. The lawsuit is the first of its kind in California and possibly the country, as school systems come under increasing pressure from parents and politicians to end online learning. With support from Mayor London Breed, City Attorney Dennis Herrera sued Wednesday. Teachers unions in many large school districts, including San Francisco, say they won’t go back to classrooms until they’re vaccinated. School administrators called the lawsuit an embarrassment and said they’ve been fighting to get kids back in classrooms.