San Antonio ? Ninth grade, often the first year of high school, is a critical time when many students sink or swim while coping with new academic responsibilities and learning the oh-so-important social hierarchy.

Some educators are turning to ninth-grade-only schools to separate 14- and 15-year-olds from older kids and make the transition easier.

“People just really value having our ninth-graders have a chance to develop intellectually, emotionally and socially outside of the context of a large comprehensive high school setting,” said Kenneth Graham, superintendent of Rush-Henrietta Central School District near Rochester, N.Y. “They don’t have upperclassmen in the halls picking on them and teasing them.”

There were 127 ninth-grade-only public schools in the 1999-2000 school year. By the 2005-06 school year, that number had jumped to 185, according to the U.S. Department of Education’s National Center for Education Statistics.

In San Antonio, the Southside Independent School District is opening a ninth-grade school this month. Another district plans to open one next year.

“I think that most of us in the state have always been looking for ways of addressing the dropout issue and … keeping our students engaged,” said Juan Antonio Jasso, superintendent of Southside.

The ninth-grade year is crucial to success in high school. If students don’t get the credits needed to move on to 10th grade, they can fall insurmountably behind. In Texas in the 2005-06 school year, 16.5 percent of ninth-graders – the highest rate of any grade – didn’t complete requirements to advance, according to a Texas Education Agency report.

Ninth grade is also when most problems start to appear, said James Kemple of MDRC, a New York-based social policy research organization.

“It’s the point where you can very clearly predict who’s eventually going to drop out,” said Kemple, director of the group’s K-12 education policy.

There are more ninth-graders in U.S. high schools than any other class. Many students either aren’t promoted to 10th grade or drop out.

In 2003-04, there were nearly 4.2 million ninth-graders nationwide. But by the next year just 3.75 million were in the 10th grade, according to the Washington, D.C.-based National High School Center.

Ninth-grade-only schools make some sense, said Joseph Harris, director of the center. But simply moving students to another campus, building or wing isn’t enough.

“It isn’t replicating the practices of a large comprehensive high school in a stand-alone ninth grade,” Harris said. “The key there is making sure that you’re facilitating the communication between teachers and administrators in ninth grade who are preparing students for eventual promotion.”