Sitting among his tiny charges, Zachary Duberstein seems more playmate than principal. Yet, behind the childlike smile and exuberance, Duberstein, a self-described "edu-nerd," is quite serious about his goals as Vare-Washington School principal - raising the level of education for its 385 elementary students, and improving satisfaction among the 51 staffers.

As a first-time principal this school year, the Passyunk resident immediately instituted changes in the schedule and makeup of the instructional block and bought $10,000 worth of books for intensive novel study.

All at the ripe old age of 27.

Duberstein is part of a growing number of young principals who - despite, and sometimes because of, their lack of experience - are bringing enthusiasm, optimism, energy, and new skills to their schools. The millennial principals, some younger than 30, also face challenges - proving themselves to staff, students, and parents; prioritizing time management; dealing with budgets; and becoming visible in the community. They have landed the top jobs after making their mark as teachers, climbing the ranks through principal-training programs, or finding themselves in the right place at the right time.

Duberstein welcomes the doubts others may have about him. "When people first see me, they have preconceived notions," he said, "but if you show them you can walk the walk, you can overcome that barrier."

Like many of his peers, Duberstein wasn't planning for the principal's office. As an undergraduate at Miami University of Ohio, he was headed for med school. After taking a course in which he educated students about basic health and wellness, he had what he described as an inner calling. "If I chose to become a doctor, I could treat one patient at a time, but through education, I could impact and transform the lives of individuals for generations upon generations to come. Education is the best preventative medicine."

That led him to Teach for America after graduation, where he spent two years in a Kansas City high school while earning his master's in special education at the University of Missouri, St. Louis. Next stops were Philadelphia's Hardy Williams Elementary Mastery Charter School as assistant principal of special education services then William D. Kelley Elementary as a principal trainee.

Hiring young principals makes good sense for the times, said Larry Mussoline, superintendent of the Downingtown Area School District, where three of its 16 principals are younger than 40.

"When you think of the traits we need as educational leaders in 2016, you want people who are a little idealistic, collaborative, socially active, highly driven, tech savvy - this is the first group growing up with Facebook and Twitter," he said. "We're looking for someone who understands digital content and can traverse the digital environment."

Sometimes, the situation is as simple as supply and demand. The number of students who earn education degrees and actually enter the education field is half what it was 10 to 15 years ago, Mussoline said.

"When there are principal vacancies, there's a limited pool of applicants," said Joseph Clapper, assistant executive director of the Pennsylvania Principals Association. Though the group doesn't compile specific statistics, "anecdotally," he said, "we are observing more and more educators beginning their first principalship under the age of 30 and an increase in educators entering their first principal position after they complete their required five years in the classroom."

Of the 27 principals in the Camden City School District, a handful are younger than 35, said Katrina McCombs, deputy superintendent. Still, candidates must have at least three to five years' teaching experience, as well as administrative and leadership experience. "They need to show they have the potential to be key turnaround principals of schools that may be low-performing," she said.

Most important is whether they will be a good fit with the school and community, McCombs added. The role of principal has evolved. Though logistics and operations are still important, there's more focus today on offering instructional leadership.

"Our younger leaders come with the most current knowledge base of the best practices in education," McCombs said.

They also are happy to get their hands dirty.

Principal Philip Schaffer, 28, eagerly led Wildwood Middle/High School's pep rally in the fall, the first for the school in almost a decade. The principal put on a mullet wig and 1970s football gear.

"By the end," said Schaffer, of Petersburg, N.J., "the kids were throwing pies in our faces."

It's part of his effort as a first-year principal to refocus and reenergize the climate and culture for its 400 diverse sixth through 12th graders and 65 staffers.

He plays a role in the school play, helps out at team practices, and takes his lunch with students. Beyond the fun and games, he has directed a redeveloped grade scale - next year, GPAs will be out of 5.0 vs. the current 5.5 - and added course offerings, including up to 27 college credits, to keep students and teachers motivated.

Schaffer arrived after five years of teaching special education and math and coaching soccer and basketball at Jordan Road, a middle school in Somers Point, and Cedar Creek High School in Egg Harbor, before taking a one-year job in 2014 as Wildwood's assistant principal/athletic director. When the principal became superintendent, Schaffer was promoted to principal.

"I don't have that experience," he said, "and I need to make sure I prove myself to the kids and staff that I belong here."

Schaffer depends on mentors, including his superintendent, for daily advice, from education law and the vision for programs to plans for the physical building and arranging a 100th anniversary gala.

So does Bobbie Downs, 30, principal of 24 middle school students at Burlington County Alternative School (BCAS). "I have a willingness to take risks and try new things," said Downs, who teaches mindfulness and yoga to her students.

Downs, who became principal in January 2015 and who lives in Toms River, said her biggest challenge was learning to balance all of her responsibilities, including pursuing her doctorate. "I'm also learning to find my own voice, to establish myself as a professional and somebody people look to as a leader."

Her original plan to attend law school was stymied when, on a gap-year trip overseas to Cairo, she taught Sudanese refugees. Realizing education was her true calling, she went back for a teaching degree and a master's in education. After she taught history for five years, BCAS expanded to include a middle school program, and Downs was promoted.

Michael Gomez, 42, now principal at Cristo Rey High School in North Philadelphia, became a principal 10 years ago at St. Joe's Prep. Looking back, "I had this ideal of a Jesuit high school principal in my mind, and I tried to act like this very experienced, very mature principal, rather than just trying to be myself."

His best advice: "Hit the ground learning. You need to learn the culture and the people rather than trying to bring about these great changes right away. And it's OK to say you don't know something, that you need help."