Local draft boards may refuse to give deferments to undergraduates who are in the bottom quarter of their class if the present military build up continues through the next six months, the Massachusetts director of the Selective Service System said yesterday.

"At the moment we have no orders," John C. Carr said in an interview, "but indications are that we will have to what we did during Korea and get reports on a student's academic standing."

"If a Massachusetts student is in the lower fourth of his class," he said, increasing manpower requirements will force his board to consider reclassifying him "certainly by next spring."

Interviews with Selective Service directors in seven other states revealed that many boards across the nation may be forced to adopt a similar policy making academic standing a criteria for deferment.

If a student doesn't maintain a C average, a spokesman for the Arkansas state headquarters said yesterday, "we'll pull him in at the end of the semester." Boards in Utah and Oklahoma have also begun selectively reclassifying students who fall to maintain a C average or better.

Officials in New York, Vermont and Illinois, however, foresaw no immediate need for drafting undergraduates. "If the present build-up continues" Col. Francis Woodworth of Illinois said, "we'll have to find more manpower somewhere, and the boards have already started tightening up on deferment. But we don't look for any wholesale reclassification."

Since local boards are required by law to grant deferment to men whose activity is "in the national interest", they enjoy wide discretion in granting 2-S status. During the Korean war, they inducted students who were in the bottom quarter of their class, but made exceptions for students pursuing degrees in physics, engineering and other sciences.

Under the pressure of increasing quotas, boards have recently begun drafting students who take more than four years to complete their B.A. and graduates who are pursuing their second degree.

Tighten Standards

"We don't like to draft students, Carr said yesterday, because its in the national interest that they stay in school -- regardless of their rank in class." He said that most draft boards hope to fill their quotas by other means, such as tightening the physical and mental standards necessary for 1-Y classification and making married men eligible for induction."

"But come springtime," he said, "the pressure of increasing quotas may force the boards to begin asking the colleges for transcripts".