WILMETTE, Ill. (CBS) — Teachers, students and staff at a Wilmette school are seeing double, and with good reason.

The fifth grade at the Highcrest Middle School is claiming the world record for the most twins in one grade of a single school.

District 39 Supt. Raymond Lechner gives twins Ryan and Luke Novosel credit for discovering the old record of 16 in one grade when paging through a copy of the Guinness Book of World Records that Ryan received for Christmas one night in January as Ryan read in bed. They immediately told their parents. Their dad, Mike Novosel, looked through the school directory and counted 23 families with “5-5” after their names, denoting two children in the same grade.

Mike Novosel contacted Guinness Book editors, who in turn demanded proof in the form of birth certificates, school registrations and a photo of all 46, which will be shot Wednesday.

There are some oddities. While all were born in the post-9/11 spike in births, only one set are believed to be identical, the rest fraternal. One set was born on different days – a few minutes either side of midnight. But the Novosel twins’ mother, Nancy Fendley, said Guinness has raised no red flags so far.

Lechner said he expects District 39 to update the record each year, if possible, as they move from Highcrest into Wilmette Junior High School. The Novosels said they already plan to resubmit for the record when they arrive as freshmen at New Trier Township High School, assuming that other feeder schools from Wilmette, Glenview, Winnetka, Glencoe and Northfield have other sets of twins.

The National Center for Health Statistics, quoted in a story for the New York Times, said between 1980 and 2009, the rate of twin births increased by 76 percent. About one in 30 babies born in the United States is a twin.

The study credits most of the increase to the increased use of fertility drugs.

That doesn’t explain why so many twins are enrolled at Highcrest, although Fendley said about half of the twins began their schooling in Wilmette at Central School in east Wilmette. Three elementary schools feed into Highcrest, which is District 39’s only middle school, for 5th- and 6th-grade students.

Some of the twins, such as the Novosels, say one can begin a sentence and the other can finish it, but that’s not the case with all of them. Aidan and Maeve Holmberg can remember sharing the same dream once in their 11 years – a scary one – but their taste in sports is different, even though they play on the same Little League team.

“We don’t really have the same thoughts, but some people say we look alike, which I really don’t see,” Aidan said.

“He’s more of a hockey fan and I’m more of a baseball fan,” Maeve said. “We both like football.”

Ryan Novosel said he didn’t want to spread the word, at least until the Guinness editors began to ask for documentation on the new record and many parents had to obtain duplicate birth certificates.

Even with 18 5th grade sections and 480 students overall, scheduling can be a nightmare for principal David Palzet, who said some parents want their twins together and others don’t.

“We try to honor their wishes the best we can,” he said.

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