According to the Daily Breeze, Jeffrey Simonek, 28, of Torrance, is facing 20 charges of lewd acts upon a child under 14 years old.
Investigators say two of the victims were students at Center Street School in El Segundo where Simonek taught fifth grade.
Simonek was also suspected of similar crimes at a camp in Northern California, investigators said. Police said Simonek has also taught and volunteered at other schools and camps in L.A. and Orange counties. He also sometimes babysat, police said.
Simonek was arrested Nov. 26, but the indictment was recently unsealed. He is being held on $20 million bail.
The Associated Press contributed to this report.