The Arlington School Board, which is facing an estimated $66 million in needed repairs and improvements to school buildings, plans to discuss tonight whether to hire a financial consultant to advise it on a possible bond issue.

Also to be discussed is the hiring of a facilities consultant who would help rank the renovation projects in order of priority and generally oversee the capital improvements plan. Total costs for the consultants would be $62,000 for this year, according to a memo to the board from School Superintendent Arthur W. Gosling.

If the School Board decides to hire the consultants, it must request extra funds from the Arlington County Board. A vote on the issue has not been scheduled.

A report done last year said the school system's 37 buildings and 600 acres will need $66 million in repairs during the next two decades. Projects range from replacing windows and plumbing to retrofitting schools to meet new needs, including extended days, and increased special education and adult education programs.

"We have what our needs will be for the next 20 years," said Tom Weber, assistant superintendent for operations for Arlington schools. The role of the financial consultant would be to help school officials decide financing options, "how to package a plan, whether to pay as you go, have one large bond issue or several small bond issues," Weber said.

Although most school officials, including Gosling, have said a bond referendum is likely, a final decision on whether to put the issue before voters has not been made, Weber said.

The earliest a bond vote could take place would be November 1988. It would be the county's first school bond referendum in more than a decade. The last two school bond referendums were in 1973 and 1975. Both were turned down by the voters.

Tonight, the board also will hear a report on minority achievement programs and discuss proposals for this year's programs.

About $130,000 was budgeted last year for a variety of school programs aimed at upgrading the performance of black students. Projects varied according to individual schools and ranged from activities to improve math performance to improving pupils' self-esteem.

Assessment reports from each school generally reported gains in mastery of subjects, a decrease in suspensions and greater parent participation.

The School Board has already approved $160,000 for minority achievement programs this year. A screening committee of teachers and administrators has recommended that 15 schools receive about $131,000 for their programs. The committee has proposed spending the balance of the funds on countywide staff development workshops and a symposium on black achievement.

The financing proposals will be voted on at the board's next meeting Sept. 10.