WASHINGTON – Students in Maine and across the country improved their performance on Advanced Placement exams last year, leading an increasing number to graduate high school with college credit, according to a report released last week.

AP classes enable high school students to earn college credit in 37 subject areas, with many colleges offering credit for exam scores of 3 or higher out of a possible 5. The courses span the academic year and culminate with an exam in May.

Kimberly Johnston, senior associate director of admissions at the University of Maine, said the university typically awards credit for scores of 3 or above, though standards vary depending on the course.

“AP courses are part of what we consider when we’re looking at the rigor of a student’s curriculum,” Johnston said. “But we certainly do not require any [AP course work].”

In Maine last year, 3,048 members of the Class of 2006 took an AP exam while in high school, up from 1,809 in 2000, according to a report released last week by The College Board, a nonprofit association focused on college admissions and exams.

Generally 50 to 70 percent of Maine students in the Class of 2006 who took an AP exam received a passing score of 3 or above.

“All 50 states and the District of Columbia increased the percentage of students who succeeded in AP courses,” Gaston Caperton, president of The College Board, said at a press conference.

Currently, 112 public high schools out of 123 in Maine offer the advanced courses, said David Connerty-Marin, communications director for the Maine Department of Education.

In 2006, the state successfully addressed the problem of the comparatively low number of American Indian students taking AP exams, a goal previously accomplished among the Hispanic student population in 2000 and again last year. However, AP participation among black students remains below the national average, according to data from the Maine Department of Education.

Phil Pratt, associate director of institutional studies at UM, said about 20 percent of the university’s first-year students entered the school with some form of AP credit last year.