Three years after it first encouraged science teachers to raise doubts about evolution, the Ohio Board of Education reversed course Tuesday, voting 11-4 to drop a much-disputed curriculum standard that became a model for several other states.

Since 2002, Ohio’s 10th-graders have been required to learn how “scientists continue to investigate and critically analyze aspects of evolutionary theory.” The theory of evolution was the only scientific discipline singled out for critical analysis.

Mainstream scientists opposed that curriculum standard at the time. But they did not threaten a lawsuit or publicly force the issue.

In the last two months, however, opposition to the standard re-emerged.

First, Ohio board members took note of a federal judge’s pro-evolution ruling in December in Dover, Pa. The judge declared that it was illegal for the school board to require teachers to introduce intelligent design, the concept that life is too complex to have evolved by random mutation.

Then a group opposing Ohio’s standards obtained documents showing that state Department of Education staff and outside scientists vigorously condemned a model lesson plan that was supposed to train 10th-graders to critically analyze evolution. These experts described the lesson plan as grounded in religious accounts of the world’s creation, rather than in science.

“I’m very pleased that the board acted decisively,” said board member Robin Hovis, who has opposed the critical analysis requirement from the start.

Hovis and others who support teaching evolution alone predicted that Ohio’s decision would affect science standards in several other states. New Mexico, Minnesota and Kansas also require students to learn criticisms of evolution; South Carolina and Michigan are considering a similar measure.