When Ellen Fox realized she no longer knew every student and parent at the Montessori Academy in Delran by name, she decided to step down from the only job she has ever had.

It took 56 years. Now, Fox, 82, is retiring from the Burlington County school she started with her former husband and a small group of parents in 1965. The school has grown from two rooms that housed 15 students into a sprawling 11-acre campus with meadows, nature trails, and farm animals.

”I love it here,” Fox said Thursday on the eve of her last day as the head of the school. “I’ve had a good life. But it’s time.”

Fox was a young, stay-at-home mother with six children when she began meeting with other mothers in their Willingboro neighborhood in 1963 and decided to form a study group. They learned about the Montessori teaching style that allows students to select the task they want to focus on and encourages curiosity, and they decided to start a school. A few women dropped out of the group because, as they told Fox, “my husband said no.”

”Times were different then,” Fox recalled.

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Fox pushed ahead. There was plenty of interest, little money. The group rented those two rooms in the Corpus Christi School in Willingboro, plus a bathroom and a playground, for $45 a month.

The not-for-profit school couldn’t afford its own telephone line so it made do with Fox’s home phone. For years, Fox didn’t take a salary, struggling to pay the staff. Her husband at the time, Charles Keith, supported the family with his trucking job. The couple divorced in 1979.

”There was no money to be made,” Fox said. “Everything went back into the school.”

A year later, the school moved into New Covenant Presbyterian Protestant Church in Rancocas Woods and later moved to its current location, initially renting space in the Barns Center on a former farm on Conrow Road in Delran. The barn at the time had already been put to use for art classes and concerts.

The school purchased the property for $150,000 in 1969. The school has expanded over the years from just a few classrooms on the first floor of the barn and now it has three stories of classrooms, kitchens, greenhouses, and gardens. Animals that roam the property are tended by students.

Today, the private, independent school enrolls nearly 100 tuition students — toddlers along with primary and elementary schoolers. It is the oldest Association Montessori Internationale-accredited Montessori School in New Jersey.

“God did it for me,” said Fox. ”I can’t claim that I was such a shrewd businesswoman.”

On Thursday, Fox spent time in front of the school assisting a group of girls planting flowers. A dedicated gardener, she enjoys sprucing up the sprawling grounds, riding around on her golf cart to pick up limbs and debris.

”It’s a little bit sad that she’s retiring,” said second grader Aaria Chakrabarti, 8, who was enrolled in the school at 18 months. “She’s funny and a nice lady.”

Fox lives on the property in a two-story, red-brick Victorian with two Border Collies and her daughter, Jennie Keith, 56, who will succeed her as head of the school. The close proximity will make it easy for Fox to volunteer and stay connected to the school. She will also maintain a second-floor office with a pillow in her chair that says “It’s good to be queen.”

As she walked into an elementary classroom, Fox was warmly greeted by students. Teacher Mericke Safka interacted with several students studying on the floor. Other students did independent learning or worked on math problems or science fair projects.

”We learn at our own pace,” said Chakrabarti, of Moorestown. “It’s a different way of teaching.”

The classroom activities reflect the essence of a Montessori education, she said. Montessori emphasizes repetition and the use of concrete objects, like beads, puzzle pieces, and tools to teach.

“The whole idea is for them to develop their independence,” Fox said. “They are responsible for their education.”

Fox has never been a teacher, but obtained Montessori training as an administrator, traveling to Italy where the Montessori educational method was started by Maria Montessori, a physician, in the 1900s.

“She‘s very knowledgeable,” said Safka, 52, a teacher at the school for 20 years. “She’s been wonderful to me.”

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Fox, who has been slowing down lately, said she began thinking about retirement after she turned over screening student applicants to a staff member. That meant she no longer met parents and prospective students during interviews, and that saddened her.

Her daughter, born 10 days after the school opened, looks forward to following in her mother’s footsteps. At work, she refers to her as “Ms. Fox.”

”I call her Mom at home,” Keith, the youngest of seven, said with a smile.

Fox was scheduled to give her final commencement address Friday night. The school planned to surprise her with a video tribute, a magnolia tree, a stone garden bench, and a serenade of The Sound of Music’s “So long, farewell.” The main building will be renamed the Ellen Fox Hall.

Fox said she was proud of her work for more than five decades. After shoulder surgery next week, she plans to spend more time gardening and enjoying her 19 grandchildren and 10 great-grandchildren.

“I couldn’t have sold TVs,” she said. “I needed something I believed in.”