Students in Virginia will find it easier to collect college credit before graduating from high school because of an agreement signed yesterday by representatives of 63 of the state's public and private universities and community colleges.

High school students could bank as many as 13 credit hours -- the equivalent of one semester's worth of courses -- by taking accelerated classes in biology, psychology or U.S. history. The partnership, in the works for about a year and affirmed by college administrators at a ceremony in Richmond yesterday, guarantees that Virginia colleges will honor the credits high school students earn in Advanced Placement courses, the International Baccalaureate program or classes at community colleges. Colleges began accepting the credits under the agreement this year.

Shaving a semester off students' time in college could save families an average of $5,000 in tuition, said Gov. Mark R. Warner (D). The program also could help ease crowding expected at Virginia colleges and universities as the number of applicants increases each year.

Many schools allow students to earn college credit while in high school, in many cases by receiving a score of 3 or better of a possible 5 on AP exams. The agreement standardizes a system whose rules have varied from school to school, Warner said.

"This makes very real the opportunity that's now available in every high school in Virginia," he said.

Warner announced last week that he will use his chairmanship of the National Governors Association to push for high school reform nationally, particularly by making 12th grade more challenging and meaningful. The partnership represents Virginia's contribution to the effort, and Warner said he hopes that institutions elsewhere will take notice.

"The next step would be to get the Harvards and Yales and schools around the country to pick up on this as well," he said.

The Virginia agreement is one of several efforts nationwide to address the twin pressures of rising tuition and growing student enrollments, said Travis Reindl, a policy analyst for the American Association of State Colleges and Universities. He said cooperation among institutions to tackle the issues is a "movement that's really hitting its stride."

At the University of Virginia, one of the agreement's signatories, Provost Gene Block said the program will not change the way the school treats freshmen. College literature reports that 60 percent enter with at least some advanced credit. But Block said the agreement shines a spotlight on options for seniors to get an early start on their college educations.

"As parents, we've all seen what happens in the last semester of 12th grade. [Students] could be doing a lot more preparation if the culture changes, and they become more focused on getting college credit," he said.

Gathering credits in high school is helpful for those who plan to spend a full four years in college, he said, allowing them to bypass entry-level courses and "drill more deeply into subject matters at the university."

About 75 percent of Virginia high schools offer Advanced Placement courses. Other students can take classes through the new "virtual Advanced Placement school," which gives them access to courses online. In the next five years, the state's community colleges hope to triple the number of students who are enrolled dually at a high school and a local two-year college, said Glenn DuBois, chancellor of Virginia's community college system.

Twenty-four private colleges and every public college except the Virginia Military Institute are participating in the program. The governor's office said the institute did not sign on because of its specialized curriculum.