The president of the National Caucus of Black School Board Members yesterday criticized the Montgomery County School Board's majority, saying its vote eliminating a mandatory black culture course for all school employes was "ill-advised" and "destructive."

Barbara Lett Simmons, a District of Columbia School Board member and head of the 2,000-member caucus, urged the county board's majority members, Marian Greenblatt, Joseph Barse, Eleanor Zappone and Carol Wallace, to "reconsider this matter before further damage is done to racial harmony and academic excellence" in county schools.

Simmons said that unless the majority reverses its decision, she will introduce a censure resolution at an April convention of the National School Board Association in Miami, which some county board members plan to attend.

Although Simmons said she had not surveyed the opinions of other caucus members, she stressed that her views represented the group "because I am the organization's titular head."

Last week the county's Human Relations Commission censured the board, accusing it of "blatant insensitivity" to county race relations.

The board's majority members have called their action a compromise. They established a mandatory 1 1/2 day minority education course for school staff and made the black culture course strictly voluntary for the system's 12,000 employes.