Fairfax County School Superintendent Robert R. Spillane asked the School Board last night to approve a referendum on the sale of almost $140 million in bonds this year to finance construction of seven new schools and renovations or additions to 32 others.

The board also approved new calendars for the 1986-87 and 1987-88 school years that would begin classes after Labor Day as a new state law requires. The board voted to retain the current five-day spring break. School will end next year on June 16.

If approved by the board May 8 and cleared by the County Board of Supervisors, the proposed $139.9 million bond sale would go to county voters in a referendum on the Nov. 4 ballot. A public hearing on the proposal will be held May 6.

The construction is needed because of population growth, especially in the lower grades, and because recently installed special programs require additional classrooms, according to school officials. The construction would account for most of the School Board's recently approved five-year capital plan for 1987-91.

Projects in the proposed bond issue would include seven new 36-room elementary schools, most in the fast-growing western area of the county. The district plans 10-room additions at Pine Spring and Kent Gardens elementary schools, and six-room additions at Glen Forest, Spring Hill, Herndon, Timberlane, Churchill Road and Parklawn elementary schools.

The district also plans to renovate six elementary schools -- Washington Mill, Canterbury Woods, Stratford Landing, Hybla Valley, Mount Vernon Woods and Springfield Estates -- and two intermediate schools -- Twain and Cooper. Nine high schools would be renovated to varying degrees -- Falls Church, Jefferson, Langley, West Springfield, Annandale, Lee, McLean, Madison and Stuart.

Gymnasiums and music rooms would be added at 11 schools, including four that also will be renovated. Three special education centers would be built.

Next year's school calendar will begin classes Sept. 2, the day after Labor Day. The board rejected a staff proposal to shorten spring break to three days. The suggested shorter break drew objections from some parents, teachers and students, although other students argued they would rather finish school earlier in return for a shorter vacation.

The board also heard from seven speakers -- six adults and a student -- who protested the ban on the use of Confederate symbols, such as mascot "Johnny Reb" at Fairfax High School. Black parents argue that the symbols represent racial discrimination and discourage their children from participating in school activities.

The speakers, to the applause of about 75 supporters in the audience at Luther Jackson Intermediate School in Falls Church, said the Confederate battle flag and mascot stand for bravery, devotion to duty and perseverance. They protested Principal Harry Holsinger's decision to ban the symbols without consulting students or parents and said they had collected nearly 3,000 adult and student signatures backing their cause.