These 300 kids left school. Then they marched down Broad Street to reclaim their education.

Hundreds of Philadelphia teenagers took over a small stretch of North Broad Street on Thursday — walking, clapping, waving flags, dancing, and reclaiming their educations.

YouthBuild Philadelphia Charter ended its “Mental Toughness Week” — a precursor to acceptance to the school — with a march to Philadelphia School District headquarters: 300 students, staff, and supporters setting an intention of making it to graduation.

Among the 300 was Jabriel Jackson, declaring his determination with his feet on a nearly two-mile walk from YouthBuild, at Broad and Dauphin, to district headquarters near Broad and Spring Garden.

Jackson, 19, left another charter school when he found out he was going to be a father. He had always felt aimless in school.

“I’ve always been good with my hands, but the schools I went to never really taught me about stuff I wanted to learn,” Jackson said. “Here, they care about you and your future.”

YouthBuild was designed to get formerly disengaged students to graduation, built around hands-on learning, industry credentials, and intensive supports for the obstacles teens in the nation’s poorest big city face on the path to diplomas. Thousands of students drop out of city schools every year.

More than 1,400 students applied for YouthBuild seats. About 300 made it to Mental Toughness Week — five days exposing them to YouthBuild’s culture and expectations. If they persisted, made it to class on time every day, they were in.

Jackson was sweating it. He loves YouthBuild already — he feels supported by the staff, he said, and is looking forward to learning construction skills — but on Friday morning, he was late to class because he had to take his 1-month-old daughter to an appointment.

YouthBuild staff met him at the door, hustled him to his classroom, told him he was OK.

“They gave me another chance,” Jackson said. “I want to make sure I don’t make them regret it.”

The walk, under a warm late-summer sun, was joy and promise on display.

Horns honked at the mass of baby-blue shirts — random strangers sharing their support. Students carried signs they had made — “Class of 2026,” “Books Not Barriers,” and “Picking Up the Pieces of My Life With You By My Side.”

One staffer snapped her fan in time with the steady beat of a drum line. Students rang bells. One, inspired, turned three cartwheels in the Broad Street median.

“YouthBuild! YouthBuild! How y’all feel?” Le’Yondo Dunn, the school’s CEO, shouted. “Solid! Solid!” the students called back.

Making the walk with the prospective students was Tanayah Robinson, the YouthBuild Class of 2025 president.

YouthBuild lifted her up when she was at her lowest, Robinson said.

“I was going through home troubles,” she said. “My parents disappeared off the face of the earth, abandoned me.”

Robinson, who was living with her boyfriend, had moved back to Philadelphia, where she spent most of her life, from Virginia, where her parents took her after middle school. But she couldn’t enroll in school because she was 17 and had no parents but wasn’t part of the foster-care system.

She didn’t want to give up on school, though, and decided to give YouthBuild a try.

The school gives students a school year to finish, and focuses on experiential learning. If you are a carpentry student, you will start working on a blighted house on your first day of school, and by graduation, you will turn it over to a low-income family.

For Robinson, healthcare was her chosen path. She put her head down and worked — and left as a certified nursing assistant with CPR certification. Two months after graduation, she is working 40 hours a week at two jobs, with a lead on another.

What astonished Robinson about her YouthBuild experience, she said, was how staff helped her with every aspect of her life — from getting the Social Security card she needed to get a job to finding a place to live.

“They insist on perseverance, and that got me through,” said Robinson, who calls herself Big Sister General and stops by YouthBuild as much as she can, even though she has her diploma now. “There are just positive vibes here, everyone is just so loving and caring. That’s what got me through.”

After the walk was over, YouthBuild’s largest class in history gathered in a third-floor space. Dunn took the microphone. It was a big moment — the acceptance ceremony, when they would find out who qualified for the school.

Dunn, who said education was his ticket out of poverty, shared with his students the advice his grandmother always told him.

“If you are going to do something,” Dunn said, “don’t half step. Today your journeys with YouthBuild are beginning.”

That is: Every student who made the walk met entrance criteria. (Because YouthBuild is a charter, if there had been more applicants who met criteria than seats, the school would have had to hold a lottery.)

Selah Yisrael said she was ready.

“I love this opportunity,” she said. “I’m going to get as many industry certifications as I can this year.”

Jackson’s face broke into a broad grin.

“I’m so excited,” he said. “I know how much this means to my mom and the people who want me to succeed, to see me graduate.”