Washington ? For the fourth time in as many months, the Bush administration is easing the restrictions of its education law, this time in the area of testing.

The latest move — reducing the number of students a school may test without running afoul of the law — probably will cap a flurry of responses to concerns from states and schools.

The No Child Left Behind Act of 2001 requires schools to test at least 95 percent of students in math and reading. Schools also must have 95 percent participation from all major subgroups of students.

The point is to make sure that schools are accountable for every student’s progress, and to ensure that no schools have incentive to exclude lower-performing students on test days.

Under the new policy, schools will get some leeway. As long as they average a 95 percent participation rate among students over two or three years, schools will meet the law.

A school that tested 94 percent of students one year, for example, could make the mark if it tested 96 percent of students the year before. The same is true for subgroups of students.

Schools also won’t have to count students who are enrolled but miss testing, including makeup exams, because of a medical emergency.