They’re not sure if there is such a category in the Guinness Book of World Records.

Even so, a class of Raintree Montessori School elementary students may have set it: a record for “Longest List of Hand-Written Math Problems on Adding Machine Tape.”

“They’re all excited,” Nancy Haynes, their teacher, said as her students worked on the project Wednesday.

“It’s pretty amazing when you have 25-plus kids who don’t want to go to recess,” Haynes said. “They want to stay in and keep doing math.”

On Tuesday, Haynes said, her students in the lower elementary class, ages 6 through 9, started a math project.

The students got out rolls of adding machine tape. They started writing math problems onto the tape, rolling up their work as they went.

They continued writing up and rolling up problems in addition, subtraction, multiplication and division, with the answers, Haynes said.

It soon turned into a competition.

“They started out racing girls against the boys,” she said.

Raintree Montessori School students, from left, Natalie Longhurst, 8, Jinsuk Lee, 8, and Eli McCleary, 8, help try to set the world record for the longest string of math problems on adding machine tape. The students worked toward their goal Wednesday at the school, 4601 Clinton Parkway.

Students were hunting problems in books and on flashcards. Some made up their own problems.

“I saw an addition problem that was something like 55,555 plus 11,111,” she said.

On Wednesday morning the students got an idea. They decided to work together to set a world record, Haynes said.

“This is huge. I’ve been a Montessori teacher for 20 years and a traditional teacher for four years before that and I’ve just never seen such amazing long work,” Haynes said.

She said students were going to investigate if they had set a Guinness record.

But what if they don’t?

“They said we’ll go for the state record,” Haynes said. “If there are any math records for what they have done, they’ve probably broken it already. … We’ll go until they get tired.”