More than a hundred protesters and counter-protesters stood on opposite sides of a normally quiet suburban Los Angeles street on Friday.
The two groups had come for one reason: the local primary school was hosting a Pride Month event.
But they had very different views on Saticoy Elementary's choice of programming.
One group of parents had launched a boycott of the school, labelling the Pride event "indoctrination" and inappropriate for children.
But counter-protesters said the demonstration was discriminatory and that children had the right to learn about different types of families.
At one point, police had to intervene when a fight broke out among protesters. One adult received minor injuries and was treated at the scene, said Los Angeles School Police Department. No arrests were made.
A school employee who answered the phone on Friday said that Saticoy Elementary had planned to read a book to students about some children having "two mommies and two daddies".
The employee did not provide further details about the event.
Renato Lira, the director of the San Fernando Valley LGBTQ Center, took part in the school's assembly.