FOXBORO - Every sophomore at Foxboro Regional Charter School passed the math and English portions of the state MCAS tests last school year.

Results released by the state Friday showed the school was one of a handful in Massachusetts to reach the milestone.

Elsewhere in the area, the news was mixed as some schools slipped a couple of percentage points while others improved slightly.

Passing the English and math portions of the Massachusetts Comprehensive Assessment System test is a requirement for graduation in public schools.

The charter school in Foxboro saw its percentage of 10th-graders passing the math test jump from 85 percent in 2006 to 100 percent last spring. Those passing the English section ticked up to 100 percent from 97 percent.

Other area schools that had all its 10th-graders pass at least one portion of the test included Norfolk County Agricultural School with 100 percent passing in English and Bristol County Agricultural School, also with 100 percent in English.

Mark Logan, principal at the Foxboro charter school, said it is unfair to compare the scores from one year to another because it compares different groups of students.

Everyone in education knows that some classes perform better than others on a year-to-year basis, he said.

It is more productive to track the same groups of children every year to see if adjustments being made at the school are working, he said.

"You want to see sustained growth in the same students over time," he said.

Logan said he believes the scores show his school has a strong curriculum and remedial attention given to students is working.

He said the charter school invests a lot of time in professional development for teachers so they can reach different types of learners.

North Attleboro Principal Robert Gay said the results he received from the test differ from those released by the state.

The state said 97 percent passed English and 96 percent passed math. Gay said he understood the correct percentages are closer to 98.3 percent. Gay said the MCAS results put schools in a bind because they have to start tutoring students who failed for a make-up test in November, but the schools have not reached individual scores yet.

The remedial work has been successful in the past and almost every student at North Attleboro High passes the MCAS by graduation time, he said.

Seekonk High School took a dip in its percentage of sophomores passing. There, 96 percent passed English compared to 99 percent the year before. Only 89 percent passed math compared to 92 percent in 2006.

Principal Marcia McGovern said schools have not had time to analyze all the results yet. However, she said that despite the dip, Seekonk High still has a larger percentage of students scoring in the proficient category than the state average.

She also said one year's 10th grade cannot be compared to another year. She said a class of students should be tracked from year to year to see if it is improving.

The state Department of Education said scores for all grades improved last spring, ending a two-year trend of stagnant scores.