Emma Lien rose early Tuesday, then took a bus and a train from her home in the Northeast to begin her first day of college.

She's 13.

Lien is one of 130 freshman at Parkway Center City Middle College High School, a Philadelphia School District magnet that's affording students the opportunity to earn their high school diplomas and associate's degrees from community college at the same time — free.

It's the only "middle college" program in the state, and will cost the school system $4 million over four years.

Three thousand eighth graders applied for the school, an existing magnet that's re-branding itself. Principal Anh Nguyen-Brown sees the program as potentially transformative, especially since about half of its students will be the first in their family to attend college.

"A lot of times, when you talk about urban areas and some of the environments that our kids are in, they might think that college is out of reach," said Nguyen-Brown. "But now, there is no barrier or excuse for them to say, 'I can't go to college.' Now there's a school that helps them go to college while they're still in high school."

On Wednesday, Lien sported her red Parkway Middle College T-shirt, a black backpack, and a sense of wonder. Though she attended Conwell, a magnet middle school in Kensington, college wasn't much on her radar until she looked into Parkway Center City.

Lien was admitted to Northeast High's magnet program, which would have meant a much shorter commute to classes, or Hill-Freedman World Academy, a well-regarded school in East Mount Airy. But Parkway Center City felt like it would open up a new world for her, she said.

"You get to save so much money not only for you, but for your parents," said Lien, touching the college ID that hung around her neck marking her as a CCP student. "It makes me feel really responsible to be here, really intelligent."

Lien and her classmates began a mandatory summer program this week, and attended their first day of a three-credit CCP class on Tuesday — some are taking History of American Diversity, some Women in History. They will take some CCP classes during their freshman and sophomore years, and during their junior and senior years will be fully immersed in the college campus a few blocks away from their high school.

The students may participate in high school sports and other extracurricular programs, and they will have support— both at the high school and the CCP levels — to help them make the academic and social leap to college.

The program will focus on entrepreneurship and computer programming — topics chosen based on student interest and areas of job growth. Students will be eligible to earn certificates in both subjects as well as an associate's degree.

William R. Hite Jr., Philadelphia school superintendent, has long been planning the program. Hite brought a middle college to Prince George's County, Md., where he led the school system there. He counts the middle college among his best accomplishments.

Three classes have graduated from the Academy of Health Sciences at Prince George's Community College. Of the 300 students, 280 have successfully collected both college and high school credentials at the end of four years.

"In the morning, they graduated with their high school diploma, and in the evening they graduated with their college peers," said Charlene Dukes, the Prince George's Community College president, who happened to be at CCP for a meeting Tuesday.

Having high schoolers at CCP isn't new: Hundreds already take courses  through existing dual enrollment programs. But the Parkway Center City program is a watershed, according to Hite and Donald "Guy" Generals, CCP's president, a recognition that colleges can engage students early and that teens will rise to the challenge with the proper support.

For their summer program, the Parkway students will be in self-contained classes. By the fall, they'll be taking classes with everyone else. Nguyen-Brown said Parkway Center City would provide time built into the school day for college support, and the school has also teamed up with Big Brothers Big Sisters to offer mentors to students.

They'll also have support from current CCP students and recent graduates.

"It is our expectation that there will be no difference," Generals said. "In our classrooms, they are college students."

That appeals to Caleb Lee, who bypassed top Philadelphia magnets Carver High School and Science Leadership Academy to attend Parkway Center City. Lee, who lives in East Oak Lane and attended Cedar Grove Christian Academy, aspires to be a doctor and is keen on the idea of having two years of college behind him at age 18.

"They're giving me a really good opportunity to make my life better," said Lee. "I'm only going to have to spend two years in college to get my bachelor's — that's amazing."

Lee said he isn't nervous, but he's fully aware of what his school choice means.

"Almost every person in college is 18 or 23, and I'm 14," he said.

Generals and Hite said they hoped to expand the program to other schools and other parts of the city.

Friends Sheliya Davis and Aaliyah Nolan were acutely aware of what a big deal their first day was.

"I'm so nervous," said Nolan, 14.

"Can you believe it?" said Davis, 13. "I'm a college student!"