California governor Jerry Brown has signed into law a bill requiring all schools to teach about the contributions of LGBT people through history.
He signed the bill on Wednesday but did not announce he had done so until yesterday.
The move makes the state the first in the US to ensure that all children learn about figures such as San Francisco gay rights campaigner Harvey Milk.
The bill, known as the FAIR (Fair, Accurate, Inclusive and Respectful) Education Act, also bans “discriminatory” teaching material.
California law already requires schools to highlight the contributions of women, African-Americans, Mexican Americans and entrepreneurs, among others.
In a statement, Mr Brown said: “History should be honest. This bill revises existing laws that prohibit discrimination in education and ensures that the important contributions of Americans from all backgrounds and walks of life are included in our history books.”
Democrat Senator Mark Leno, who introduced the bill, said: “Today we are making history in California by ensuring that our textbooks and instructional materials no longer exclude the contributions of LGBT Americans.”
Some religious and ‘family’ groups complained about the bill, claiming that it was “politically correct”.
Others went further. Randy Thomasson, president of SaveCalifornia.com, said schools would “sexually brainwash” children.