The second-alarm fire broke out in the 3800 block of West 54th Street around 12:15 p.m. It took 75 Los Angeles City and Los Angeles County firefighters to douse the blaze. No one was inside the building at the time. Four turtles were rescued from the building. It is unclear how the fire started.
The building has been red-tagged. Firefighters say the roof on the east side of the school collapsed and there is heavy damage from front to back.
The school has been a community fixture for 46 years.
"This is devastating to us, but there is certainly a bright side, and that is we just thank God that no children were here. We thank God that no one was hurt," said Dr. Angela Massengale with Little Angels Preschool.
About 100 kids, ages 2 months to 5 years old, attend the school. There is also extended daycare for children up to 12 years old.
Students will have classes in two smaller buildings on the property Monday.