THE ARCHDIOCESE of Philadelphia agreed Monday to work more closely with the School District of Philadelphia and the city's charter-school community to ensure that the city's children have access to quality schools - a decision that could increase the city's chances of winning millions of dollars from the Bill and Melinda Gates Foundation.

In a ceremony at St. Peter the Apostle School, in Northern Liberties, Archbishop Charles J. Chaput signed an agreement that would make the city's Catholic schools a member of the Philadelphia Great Schools Compact, a collaborative education effort backed by Mayor Nutter, state Education Secretary Ronald Tomalis, the district and charter organizations that aims to add 50,000 seats in high-performing schools within five years across the city.

Catholic schools educate more than 20,000 students in the city.

Nutter called the signing "a historic moment here in Philadelphia."

He said that improving educational options for the city's more than 200,000 school-age children was essential for ensuring the region's economic future by increasing high-school-graduation and college-attainment rates.

Fifteen cities nationwide have signed compacts. Philadelphia has received $100,000 in Gates funds to help it get off the ground.

Officials also said that they expected the agreement to improve cooperative planning. Lori Shorr, Nutter's chief education officer, who chairs the compact committee, said that after the Archdiocese this year announced its plans to close several Catholic schools in the city, representatives from the Archdiocese and the school district met to consider the effect those closings could have on district schools. She said that unusual level of communication helped the district plan for the additional students.

Compact representatives also said that the agreement would make it easier for families to find information about schools through a website being developed.

Mary Rochford, superintendent of archdiocesan schools, said that the Archdiocese had agreed to make test-score data for Catholic schools public for that site.