Among the honored guests were the school's two current kindergarten classes and 18 seniors who came through the MFS kindergarten.
"I'm glad to have you here to celebrate our kindergarten's birthday," said Lower School director Kelly Goula, who said MFS's kindergarten is one of the oldest in the country.
Head of School Larry Van Meter, who entered kindergarten in 1955 and brought his report card to prove it, recalled with fondness blocks and finger-painting and his teacher's patience - a quality he said the current teachers share.
But kindergarten at MFS and elsewhere has become much more structured and academic over time. Schools may see even more changes as states, including New Jersey, have adopted the Common Core Standards intended to increase the rigor of kindergarten-through-12th-grade education nationally.
Kindergarten's roots lie in the power of play. In 1837, the educator and reformer Friedrich Froebel began a school in Germany that became known as kindergarten, or "children's garden," and emphasized learning through play, song, and other creative pursuits. About two decades later, the kindergarten concept came to this country in Wisconsin and, later, Boston.
In recent decades, research on child education and development, as well as a greater emphasis on testing and measurable learning, has spurred kindergartens toward more academic content.
"What first grade used to be, kindergarten is," Goula said.
New Jersey is among a majority of states that do not require public school districts to fund full-day kindergarten, according to the Children's Defense Fund, a full-day advocate. A bill that would create a task force to explore full-day kindergarten has been approved by the Assembly and is now in the Senate.
Indeed, many young children relish reading and developing their math skills. However, nationally, some educators and advocates worry that the pendulum may be swinging too far away from play, exploration, and imagination toward developmentally inappropriate activities and assessments.
Some, such as the Massachusetts-based Defending the Early Years, say this may be even more likely to happen in lower-income public schools and districts that are dependent on government aid.
As a private school in a relatively affluent community, MFS has the freedom to shape its own program.
"We want our kids to have a love of learning," Goula said.
A full-day program, MFS offers a day filled with topics including reading, math, "handwriting without tears," science, music, technology, and art, as well as playground time.
This week, Jody Huege, 5, a student in Audrey Tedesco's kindergarten class, said she liked her class' loft, where she and her friends read and do puppetry. She bemoaned not being able to bring her superheroes to school but said she enjoys "quiet relaxation" (nap time, way back when). She also likes learning the days of the week.
She wouldn't have guessed her kindergarten was 130 years old.
"It doesn't look that old," she said. "No cracks in the windows. I'm surprised."
At Thursday's party, she and fellow kindergartners listened to stories read by the seniors. Despite the age gap, the children bonded over shared experiences and issues.
"As you get older, you'll figure out more numbers. Don't worry," Sloane Gandler, 18, told an attentive Emma Chung, 5.
A couple of tables over, the conversation had turned to dinosaurs.
Chloe Marshall, 6, told Pierce Williams, 17, that she wanted to be a paleontologist, just as Williams did when he was in kindergarten.
"I can really relate," said Williams, who now wants to go into sports management or be an entrepreneur.
When it was time for the group photo, kindergartners crowded around the cake; the tall seniors towered behind.
Then, with the cameras on the ready, they belted out what children in class pictures have for generations: