SACRAMENTO, Calif.—Gov. Arnold Schwarzenegger on Tuesday vetoed a bill seeking to prevent a revised social studies curriculum approved in Texas from being taught in the nation's largest public school system.

The state Board of Education already has an adequate curriculum review process, and a further layer of scrutiny would be "duplicative and unnecessary," Schwarzenegger said in his veto message.

The bill, SB1451, would have required the board to look out for any of the Texas content as part of its standard practice of reviewing public school textbooks, and then submit its findings to the Legislature.

The Texas school board adopted standards in May asserting that the country's Founding Fathers were guided by Christian principles. The changes also minimize Thomas Jefferson's role in world and U.S. history because he advocated the separation of church and state, and require that students learn about "the unintended consequences" of affirmative action and Title IX, the federal law that bans gender discrimination in education