Benjamin Harold Alexander, chosen Wednesday night as the new president of the University of the District of Columbia, has established a reputation as a conservative on education issues both in his years in Washington and during his tenure as president of Chicago State University.

Between 1966 and 1969 as a member of the D.C. school board, Alexander opposed the outcry of the day for more community control of schools and busing to achieve racial balance. He also spoke out against the practice of promoting students based on their age, and of rigidly grouping them in classes based on their ability.

As president of Chicago State, a predominantly black school on Chicago's South Side, he moved in 1974 to institute proficiency examinations and traditional grades in an era when open admissions policies and pass/fail grading systems were in vogue. He expelled 130 students and placed another 1,000 on academic probation because, he said, he felt they were just hanging around the campus.

Though Alexander's no-nonsense educational theories have at times met with opposition, he now comes to five-year-old UDC at a time when the university is examining its role and seeking to establish higher academic standards.

Most of UDC's students are part-time, their average age is 26 and many of them come from the D.C. public schools. UDC has been the alternative for many public school graduates not able to attend other colleges for academic or financial reasons. The school is now faced with the dilemma of how to continue this service while at the same time improving its image and standards.

Alexander, 60, says he comes to UDC with just one mandate: "I am for a university that is going to move ahead. I would not be interested in becoming president if I were not interested in making that the Number One university in the area." He says he believes he was picked because of his record at Chicago State.

Joseph Webb, a member of the eight-member search committee that recommended Alexander, said some committee members were concerned that Alexander would oppose UDC's policy of open admissions. But Webb said Alexander was able to convince them that the school could continue open admissions while still holding students to standards.

"There are no low-level intelligent people, just people who have not been taught . . . My whole point is that everybody should be given the opportunity to go to a university, but if you can't make it, you should be directed to another area," Alexander said yesterday in a telephone interview from Springfield, Ill., where he was attending a conference.

Before going to Chicago State in 1974, Alexander had spent 20 years as a research chemist with the federal government here. During those years he served for a time as president of the D.C. Federation of Civic Associations and chairman of the D.C. Commission on Arts and Humanities.

Alexander said that when he arrived at Chicago State he began requiring all students entering the college to take proficiency exams in English composition, reading and mathematics. Under his system, those who do not meet a certain level are put in remedial classes and retested at a later date. About 40 percent of the new students are deficient in all three areas when they enter, but about 70 percent pass the test once they have received remedial help, he said.

"If, ultimately, the student cannot make it, he should be failed," Alexander told the UDC search committee.

Members of both the search committee and the UDC board of trustees praised Alexander yesterday for his administrative experience, emphasis on standards, and the knowlege of Washington and its government that he gained in his years here.

The board of trustees was split, 6 to 6, over his appointment, with board chairman Marjorie Parker casting the tiebreaking vote. Two board members were not present for the voting.

Yesterday, a group of about 30 faculty members threatened to sue the board of trustees over the procedures it used to appoint Alexander. The opposition appears to stem mainly from concern over stands Alexander has taken on racial issues, like his opposition in the 1960s to more militant black leaders and his insistence that blacks should call themselves "Americans of African heritage," because of what he sees as negative connotations with the word black.

Alexander was chosen for the post over 92 other candidates, the university said yesterday. The search committee began its work in February of last year, after university President Lisle C. Carter Jr. informed the board of trustees that he planned to resign.

Alexander received a bachelor's degree from the University of Cincinnati, a master's degree from Bradley University and a PhD from Georgetown University, all in chemistry. He is married and has two children, a son, Drew, who is now a doctor, and a daughter, Dawn, a college student.