The year that Colin McCarthy spent at the Navy Yard with high school seniors from some of the city's poorest neighborhoods turned out to be far more than just a quirky pit stop in a mid-career conversion from marketing executive to public-school teacher.

As McCarthy watched students ditch the timeworn desk rows and math drills of a traditional high school to work around a conference table on long-term, community-oriented projects, such as bringing solar power to their learning space, he grew convinced he was seeing the future of American education. And he became an evangelist.

"I want to be the Johnny Appleseed of project-based learning," said McCarthy, 49, who now is spearheading an ambitious, $350,000 foundation-backed program to bring the innovative approach to Montgomery County's Cheltenham School District next fall. He envisions its becoming a showcase for other schools in the region.

The rollout will involve 66 ninth graders, who will spend the first half of their school day on one- to two-month group projects of their own design. Their ventures will cut across traditional subject areas such as science, English, and world cultures. In the end, the Cheltenham community is supposed to see some benefit from the work the students have done.

"It's really about challenging them to solve a problem -- a real-world problem -- in the context of the curriculum," said Wagner Marseille, superintendent of the 4,700-student district and an enthusiastic backer of project-based learning.

He and other administrators, faculty, and school board members have been traveling to San Diego to observe one of the most heralded such programs in the nation, High Tech High.  Starting Monday, eight teachers will embed in classrooms there for a week.

The concept behind project-based learning goes back at least to the early 20th century and educator John Dewey's furtherance of "learning by doing." But the idea of creating programs for entire schools around less structured, real-world problem-solving and student collaboration has gained considerable traction in academic circles this decade – arguably, a reaction to the ever-increasing emphasis on standardized testing and classroom drills that clearly aren't working for all kids.

The Cheltenham initiative is based in part on the nationally acclaimed program that evolved from the Navy Yard enterprise, where McCarthy taught in 2012, into today's Workshop School in West Philadelphia.

"We're trying to prepare our students to succeed once they're in an environment where nobody is telling them what to do," said Matt Riggan, who cofounded the Workshop School.

The project-based model has been adopted by a few other area schools, among them the city's Science Leadership Academy, a district school that collaborates with the Franklin Institute. It also can be found in Big Picture Learning schools that include the Camden Learning Academy and three other schools in New Jersey, as well as El Centro de Estudiantes, an alternative school for older youth in Philadelphia.

While advocates often stress project-based learning as a way to help kids falling behind in underachieving districts, more affluent, better performing districts have also adapted the approach in varying forms. Radnor Middle School's long-running Watershed environmental initiative, a yearlong program that replaces the usual seventh-grade curriculum, is open to 20 students.

In Cheltenham,  Marseille was looking for ways to revitalize a district that produced such alumni as Israeli Prime Minister Benjamin Netanyahu and baseball slugger Reggie Jackson at the height of the baby boom era. It has grown increasingly diverse in the 21st century as more African Americans, Latinos and other minorities move across the city's northern border into the inner-ring suburbs. Cheltenham raised its current School Performance Profile score, a state assessment of schools and student achievement, to 77.2 last year after three years of decline. However, the superintendent has more ambitious goals.

"We wanted to do a five-year plan that looks very different from anything they ever did before," Marseille said.

For that, the district's connection with McCarthy and the Avalon Foundation proved serendipitous. McCarthy had worked as a student teacher in Cheltenham while studying for his master's degree at Arcadia University. Perhaps more important, he had a connection to the Avalon Foundation -- a philanthropic effort launched by his father, Michael, an alumnus and booster of Philadelphia's La Salle Academy, who retired in 1999 as head of municipal bonds for Goldman Sachs.

Colin McCarthy no longer teaches, but as a grants administrator for the foundation, he worked with his father and Marseille to fashion a grant that will pay the district $250,000 in the first year of the program  and $100,000 in the second year. The long-term plan calls for expanding the program throughout the high school, then eventually taking it into the middle and elementary schools.

Students will collaborate with community leaders on projects such as a marketing program around local environmental issues, according to Marseille.  The district is busy remodeling two classrooms for project-based learning: bigger windows, a pull-down garage-style door to the outside, space for equipment like a 3-D printer and a drill press.

After mornings spent on their projects, students will take traditional classes in standard subjects in the afternoons. That hybrid approach, experts say, reflects the tension between excitement over a new, unconventional approach to learning and the desire of college admissions officers for advanced-placement grades or other traditional metrics of student achievement.

"The most common criticism is that it's just sort of all touchy-feely and there's no rigor there," said the Workshop School's Riggan. He said he understands the desire for more traditional sequential learning in math, but strongly defends a curriculum built around practical problem-solving, not standardized tests.

In Cheltenham, McCarthy envisions the foundation's seed money growing a program that can be adopted by other Philadelphia-area districts such as Upper Dublin, where his  three children attend school.

"I'm hoping to do it very locally," he said of his agenda, "so we can support each other."