The Arlington School Board voted unanimously early today not to close any secondary schools and to keep the current grade configuration that groups students in elementary, intermediate and high schools.

Early today the board was still debating the fate of eight elementary schools considered for closing or merger under a plan by School Superintendent Charles E. Nunley. The board appeared to favor closing Claremont Elementary and sending its students to Abingdon Elementary, but was still uncertain about plans for closing schools in North Arlington.

At a series of recent public hearings, angry parents repeatedly asked the board not to close their neighborhood schools. The board has been considering closing as many as six schools by the end of the 1984 school year because of declining enrollment.

Board member Michael Brunner, echoing his colleagues' reasons for choosing not to close any secondary schools, said, "I can't find any reason to close them." He said secondary school closings offer no instructional benefit and uncertain financial savings.

In other action, the board took a first step toward tightening high school attendance and open campus policies. It directed Nunley to prepare a plan that would require students to remain on school grounds for the entire school day and would limit the number of allowed unexcused absences.

That action came after Arlington Commonwealth's Attorney Henry Hudson repeated a request his office made two years ago that the board revoke policies allowing students to leave school grounds during lunch hours and free periods and grant students 10 unexcused absences without loss of course credit. Hudson told the board that the policies contribute to juvenile crime and drug use.