(CNN) -- Fresh on the heels of a new immigration law that has led to calls to boycott her state, Arizona's governor has signed a bill banning ethnic studies classes that "promote resentment" of other racial groups.

Gov. Jan Brewer approved the measure without public statement Tuesday, according to state legislative records. The new law forbids elementary or secondary schools to teach classes that are "designed primarily for pupils of a particular ethnic group" and advocate "the overthrow of the United States government" or "resentment toward a race or class of people."

The bill was pushed by state school Superintendent Tom Horne, who has spent two years trying to get Tucson schools to drop a Mexican-American studies program he said teaches Latino students they are an oppressed minority. There was no immediate response from the Tucson Unified School District, the law's main target.

Brewer's signature comes less than a month after she approved a state law that requires immigrants to carry their registration documents at all times and allows police to question individuals' immigration status in the process of enforcing any other law or ordinance. Critics of the law say it will lead to racial profiling, while supporters say it involves no racial profiling and is needed to crack down on increasing crime involving illegal immigrants.

On Wednesday, the Los Angeles City Council overwhelmingly approved a boycott of Arizona-based businesses and governments unless the state repeals the new immigration law.

The city's legislative analyst reported that Los Angeles currently has $56 million in contracts with companies headquartered in Arizona.

Several other California cities, including San Francisco and Oakland, have already adopted resolutions requesting city departments to not sign any new contracts with Arizona companies.

City also bans employees from travel to Arizona

CNN's Alan Duke contributed to this story.