Rachel Hathhorn thought she was seeing double at Wexford Elementary - and she was.

As communications director for Pine-Richland School District, Ms. Hathhorn was taking a photo at the K-3 school in Pine when she noticed two sets of twins.

She asked about it and discovered the school has 18 sets of them - about 8.5 percent of its enrollment of 447 are sets of twins. And there's one set of triplets.

First-grade teacher Maura Berger, like so many others, was amazed to learn of the number of twins at the school.

"It's funny. I didn't realize Wexford has that many," said Ms. Berger, who has a unique perspective because her two sets of twins are part of the school's enrollment.

The birth rate for twins in the United States is 32.2 per 1,000, according to 2006 statistics from the Centers for Disease Control.

The rate of twin births has been climbing steadily. The National Center for Health reported that the U.S. birth rate for multiples rose 28 percent between 1990 and 1998 to 29 per 1,000. The reasons included the increased use of fertility drugs, in vitro fertilization and "older" moms, women who have had children in their mid-30s or later. Waiting later in life to have children, among other things, increases the chance of having twins, according to the Health Statistics center.

After learning about Wexford's twin population, Ms. Hathhorn decided to take a second look at the registration for all the schools in Pine-Richland. They all have twins, she found, and some have triplets and quadruplets. At Richland Elementary, there are five sets of twins and two sets of triplets in the 462 students at the school. Hance Elementary has six sets of twins, among its 381 students.

Eden Hall Upper Elementary has 1,051 students, including 20 sets of twins. There also are two sets of triplets.

For Pine-Richland Middle School's enrollment of 743, there are seven sets of twins, 2 sets of triplets and one set of quads.

At Pine-Richland High School, there are 1,428 students, including 28 sets of twins. There also are two sets of triplets.

With twins comes at least one decision other parents don't have to make, and the issue stirs strong feelings. Parents of twins are often adamant about whether their children should be placed in the same or in separate classrooms, said Ms. Berger.

In Pennsylvania, the law is on the side of parents.

Rick A. Walsh, principal at Wexford, said state law requires schools to listen to parents when it comes to decisions about putting twins in the same or separate classrooms

"They are the child's first teacher," he said. Being in the same classroom allows the twins to share the whole school experience, the principal continued. They can work on homework together and ask each other questions about what went on in class that day, he said.

Ms. Berger addressed a commonly offered reason for separating twins as they enter school: It allows them to develop individual personalities, the thinking goes.

"We know they're individuals," Ms. Berger countered. "I like to keep mine together for the management part." If her third-grade twin boys and second-grade twin girls were in four different classrooms, Ms. Berger said, she "might go nuts."

Lisa Gaffey, the mother of twins Henry and Molly, said she liked Wexford Elementary because her twins are allowed to be in the same classroom.

"Mine do quite well together. There are no issues with being in the same class," said Ms. Gaffey. "They have a very good relationship. They are each other's best friend. ... How many people are lucky enough to be born with their soul mate? Why split them up?"

With so many other multiples at Wexford, the twins blend right in, said Ms. Gaffey.

Twins do not pose a particular challenge for teachers, Mr. Walsh said. Because the teachers spend so much time with the children, they look at the children as the parents do - as individuals with unique personalities and behaviors, he said.

Mr. Walsh said he did not see any twin high jinks at the primary school level because the young children are getting used to the school experience and are focused on learning.

When he worked for another school district, Mr. Walsh said, he knew of twins in high school trying to switch classes.

"The teachers knew right away," he said with a laugh. "It didn't help that their father was the superintendent."

The high number of twins at the elementary school is "part of what makes up the Wexford family," Mr. Walsh said.

"Nobody really thinks about it," said Ms. Gaffey. "There are so many of them."

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