The D.C. Board of Education last night gave preliminary approval for creation of a new high school that would offer a more rigorous curriculum than any other school in the city.

The proposed "academic high school" for about 300 students was recommended by School Superintendent Vincent E. Reed as a method of stemming the flight of many average and above-average public school students to private schools.

The board's 5-to-3 vote gives Reed's staff the authority to work out details for the academic program, including selection of a location for the school. The new program probably would be located in an existing school, but it was not clear when it is likely to start.

The board will vote again on the proposal when Reed submits his final plan for the proposed school sometime before the end of the current academic year.

The idea of a special academic school was a divisive issue for the school board on an earlier occasion. In 1976, the idea was criticized by parents in the wealthier school districts in upper Northwest Washington, who felt an academic school would drain their community high schools of their best students. Parents from poorer neighborhoods of far Southeast also attacked the plan as "elitist."

Some of those same arguments cropped up again at yesterday's board meeting. Board members Eugene Kinlow said the board may be "raising the spectre of other than equal resources" by having one school with a more rigid curriculum than others.

One of the most outspoken board members against the proposal, Kinlow said he preferred having specialized and advanced programs within existing schools so that slower-learning students could benefit by association with brighter students.

But board member Linda Cropp said that as a former teacher she saw good students "intimidated if they tried to excel. Other students who cannot keep up with them hold the whole class back."

Board member John E. Warren said Reed's proposal was in effect creating a private high school in a public school setting. "The kinds of things laid out in [the proposal for] that high school are the kinds of things supposed to be in every high school," Warren said.

The proposal calls for limiting electives open to students, while requiring at least two years each of math and science, four years of both social science and English, and three years of a modern language and three of a classical one such as Latin. D.C. schools now have no language requirements.