By LISA FLEISHER

New York state education officials want to split the toughest mandatory exam that high-school students have to take into two—and require only one of the tests for graduation.

The proposal for the global history and geography exam Monday came in response to an outcry—largely from history teachers—that arose earlier this year after the Board of Regents considered making the exam optional. The test has the lowest passing rate of any of the five required for graduation, including math, science, English and U.S. history.

Regents Chancellor Merryl Tisch had advocated allowing students to replace the global history graduation requirement with a vocational exam, or an additional math or science subject test, to give students more options for earning a diploma.

Teachers, however, said they feared an untested subject wouldn't be taken seriously. They said it was the only test that packed two years' worth of material into one exam.

In addition, thanks to what state officials described as a quirk in regulations, the global history course wasn't technically required, though the exam was.

To address those concerns, state Education Department officials said the Regents suggested splitting the exam, making the first year about "foundational skills" in world history, geography, economics and civics, and the second about "cross cultural themes and patterns."

The required test would cover only second-year course work. They also suggested requiring two years of global history courses.

In 2011, 69% of state students had passing scores on the global history and geography test, the lowest of any required exam.

Any change wouldn't take effect until the 2013-14 school year and would come as it becomes more difficult to get a Regents diploma in New York.

Starting this year, students have to pass all five exams with a score of at least 65. Previously, they could score 55 on one or more exams and still earn that diploma.

New York City officials welcomed the changes but warned that graduation rates could take a hit once the tougher requirements are in place.

The cost of creating two new tests could be a big hurdle. State education officials said it would cost between $500,000 and $1 million just to transform the current test into a more focused version, and said they didn't know what it would cost to create another test.

Some teachers welcomed the move.

"It's a more realistic approach," said Mark Thomas of Tully, N.Y., who has taught global history. "I've always wondered why it was a two-year test to begin with. The ninth-grade class teachers are always freaked out. They have to go into the 10th grade classroom and reteach some of the things they taught before."

Corrections & Amplifications 
An earlier version of this story omitted a word from Mark Thomas' quote. The full quote has been restored.

Write to Lisa Fleisher at lisa.fleisher@wsj.com