Under the new amendments, at least 60 percent of the school curriculum, including foreign-language courses, shall be taught in Latvia's national language, Lettish, whereas the languages of ethnic minorities living in the republic may be used for no more than 40%.
Latvia's Russian-language students total 120,000, making up over one-third of the republic's student body.
The Latvian legislature has passed the amendments despite vociferous protests by members of the Russian community, including school-age children, and ignoring recommendations from international public organizations and appeals by counterparts in the State Duma, or Russia's lower house of parliament.
The amendments, which also strip private Russian schools of government subsidies, were approved by Saeima at its Thursday's session in a 71-25 vote. They will make it easier for the Latvian government to discriminate against the Russians, who form the country's second largest ethnic community, left-wingers warn.
Igor Pimenov, Chairman of the Latvian Association of Russian-Language Schools, has called on President Vaira Vike-Freiberga to send the education law back to the legislative branch for revision.