Ethnic Mongolians in northern China have staged rare rallies against measures to reduce teaching in the Mongolian language in favour of Chinese.
As schools began a new term on Tuesday some parents held children back in protest at the policy.
Under the rules, three core subjects in Inner Mongolia will gradually be taught in Mandarin, China's official language.
Many ethnic Mongolians view the move as a threat to their cultural identity.
Large crowds of students and parents were seen protesting against the change in demonstrations that broke out over the weekend across several cities.
"Our language is Mongolian, and our homeland is Mongolia forever! Our mother tongue is Mongolian, and we will die for our mother tongue!" shouted students at one recent protest, reported Radio Free Asia, a US government-funded broadcaster.
Images of women applying their fingerprints or adding their signatures to petitions against the move were also widely circulated on social media.