Enrollment figures for September 1980, released last week by the Prince George's school board, confirmed the expected decline in overall enrollment and increase in the precentage of blacks and other minorities in the county schools.

The figures showed an overall 4.1 percent drop in students, from 127,108 last year to 121,893 this year. The drop was 1,196 students fewer than school officials had estimated, largely due to unexpected enrollment 1st-7th- and 10th graders from out of state as well as from private schools within the county.

Overall, the school system lost 5,215 students. The drop represents a net loss of 6,121 white students, from 62,152 to 56,031, and a gain of 914 minority students. The number of black students rose 1 percent to 60,793. Asian students increase 7 percent to 3,414 and Hispanics rose 9 percent to 1,382. Black, Asian, Hispanic and Native American students as a group increased from 51 to 54 percent of the public school enrollment.

The changes in racial balance were most pronounced in the elementary schools, which crossed from 49 to 51 percent black. However there were wide swings in both directions in several schools affected by this year's modification of the court-ordered busing plan.

The change, ordered by the school board, was intended to eliminate some busing of elementary school students in neighborhoods sufficiently integrated to allow a return to the "neighborhood schools" closest to their homes. The direction of change in racial balance was predicted in all cases, but the size of the change was greater than estimated by the citizens' advisory committee that produced the plan.

For example, in three Bowie elementary schools -- Buckingham, Pointer Ridge and Tulip Grove -- the numbers of blacks decreased by 8 to 10 percent. rOxon Hill Elementary went from 55 to 47 percent black while Camp Springs Elementary dropped from 56 to 42 percent black.

At the same time, several schools, including Happy Acres, Rose Valley and Woodmore, took large jumps across the 50 percent line, going from 47 to 64, 38 to 54 and 39 to 56 percent black, respectively.

In other business at its meeting last week, the school board rejected a resolution by board member Angelo Castelli to require all Prince George's teachers to live in the county. Instead the board passed a milder measure that will give preference in hiring and promotion to Prince George's County residents and the alumni of its public schools "when other factors of qualification are equal."

The board also voted 8 to 1 to proceed with plans to close the Tanglewood and Ritchie elementary schools and renovate them for use as special education centers, and to renovate the closed Margaret Brent Elementary School for special education students.

Board member Bonnie Johns cast the lone dissenting vote, saying she had reservations as to whether the proper notification procedures were followed in the Ritchie closing.

Finally, the board rejected a proposal to give voting rights to the student board member for the third year in a row, voting against endorsement of a bill to be introduced in the 1981 session of the state legislature.