Nearly 900 children returned to schools in Boston and Cambridge this fall with a boost from the award-winning academic enrichment provided by the Summer Urban Program (SUP) at Harvard’s Phillips Brooks House Association (PBHA).

SUP, which is run by Harvard undergraduates and hosts 11 free summer camps in Boston and Cambridge, received the National Summer Learning Association’s 2011 Excellence in Summer Learning Award last month. The national organization supports summertime learning and rigorously assesses programs each year.

Research has established that children lose academic skills during summer breaks, and low-income students are disproportionately at risk. Education experts point to summertime programs such as PBHA’s as a way to help bridge the gap.

“PBHA’s SUP fits into a broader context. It’s helping Boston close achievement gaps by closing opportunity gaps in the summer,” said Christopher Smith, executive director of Boston After School & Beyond, a public-private partnership that supports, strengthens, and expands Boston’s after-school sector.

Smith noted that the camps make a difference for the hundreds of students they serve and the often-underserved populations they benefit, including students from international backgrounds and those who speak English as a second language (ESL), who can struggle at school.

The camps offer seven-week programs for children ages 6 to 12. Campers work on academics, including math and literacy skills, in the mornings and attend field trips, including visits to colleges, museums, historic sites, and the New England Aquarium, during the afternoons.

PBHA’s summer learning data points to progress. According to SUP evaluations, 85 percent of ESL campers have improved scores after attending the camps. Nearly 80 percent of parents reported improvements in their children’s reading, writing, and math skills over the summer. Ninety-eight percent of junior counselors (children can spend years in a program, first as campers and later as paid junior counselors) plan to attend college.

The camps are led by about 130 college students. Some are Harvard undergraduates and others are local students, most of whom participated in the program as campers and stayed on to teach or help run the camps. PBHA program directors say creating a sense of community at each camp and encouraging youngsters to be agents of change in their communities are important parts of SUP. This is why SUP offers opportunities for campers to come back as junior counselors, senior counselors, and even program directors (where they also earn a summer stipend). Harvard students and local college students work together to build that strong sense of community.

“Students regularly worked 12- to 16-hour days during the program to make sure the next day’s session was as enriching and fun as possible. … The level of collaboration among students in planning the program is remarkable,” said Sarah Pitcock, senior director of program quality at the National Summer Learning Association.

The program was also lauded for collaborating with other programs and being part of the communities they serve.

“PBHA is building communities in three levels — among the students they serve, among their staff, and at the city level, with us and other partners. They serve as a satellite summer school for Boston,” said Smith.

As for the students who plan and run the camps, being recognized among the nation’s top summer learning programs is an honor, but they say the recognition goes to all involved.

“This award is such a big honor, but we couldn’t do what we do without the community organizations, parents, and children we work so closely with over the summer,” said SUP program director Diana Bartenstein ’12. “There’s a lot of energy in the program, and all involved are really committed to it, and that makes the difference.”

SUP began in 1980 and runs day camps in the following neighborhoods. It partners with local schools and organizations to host the programs:

In addition to the camps, the program provides ESL training for immigrant and refugee teens. PBHA’s Boston Refugee Youth Enrichment and Refugee Youth Summer Enrichment have been recognized by the Boston Public Schools as alternatives to summer school. Its Native American Youth Enrichment Program is the only summer camp specifically for urban Native American youth in Massachusetts.

SUP receives support from a number of Harvard groups, including the President’s Office, Harvard Public Affairs & Communications, the Harvard Achievement Support Initiative, the Office of Career Services, and the Institute of Politics. The program is also supported by many community partners and citywide by the Boston Public Schools, the Cambridge Public Schools, the Boston Youth Fund, Action for Boston Community Development, the Boston Center for Youth and Families, and the Cambridge Mayor’s Youth Fund.

Each year, the National Summer Learning Association recognizes summer programs that demonstrate excellence in accelerating academic achievement and promoting healthy development for young people. The PBHA program was the only entirely college student-run program among the five recognized this year.