IN CONJUNCTION with the exhibition "Aditi: A Celebration of Life," the National Museum of Natural History is presenting a program called India Through Film and Lecture in its ground-floor Baird Auditorium. Friday at noon, filmmakers Rakhi and Jayasinhji Jhala will present their 36-minute documentary A Zenana: Scenes and Recollections. The zenana is the women's quarter of Dhrangadra, in northern India, and the film explores the relationship of Hindu and Muslim women within the almost closed community. The whole event is expected to go no later than 1:15.

The film (sans makers) will be shown again on Saturday and Sunday at 1, supplemented by Serpent Mother, the second film in the trilogy Pleasing God by Harvard University Film Study Center staffers Robert Gardner, Akos Oster and Allen Moore. A half-hour treatise on Manasha worship in the West Bengalese city of Vishnupur, the film will run second on both days. The National Museum of Natural History is at 10th and Constitution Avenue NW. Call 357-1607.

If you've got the urge to settle into a nice, comfy repertory theater, there are plenty of weekend options.

* The American Film Institute Theater opens its festival of Screwball Comedy with Howard Hawks' Twentieth Century (Friday night at 7 and Saturday at 6:45), a film so fast- paced you may want to bring along an oxygen tank. Richard Lester's A Hard Day's Night will share a bill with Help! Saturday at 8:30 and Sunday at 5:30 (when "Help!" will show first). Call 785-4601.

* The Biograph's latest collection on auteurs continues with two John Sayles movies, The Return of the Secaucus Seven and The Brother From Another Planet. Both films run Friday through Sunday; call 333-2696.

* The Circle Theater people continue an MGM festival at their repertory house (2105 Pennsylvania Avenue NW) with a musical double bill of Anchors Aweigh (Sinatra and Kelly) and The Band Wagon (Astaire and Charisse) through Saturday, and the literary dramas Pride and Prejudice and A Tale of Two Cities Sunday and Monday. Call 331-7480.

* The Sidwell Friends School's summer film program continues with Eric Rohmer's French social comedy Pauline at the Beach Friday through Sunday at 7:40 and 9:35. Call 537-8178.

A reminder about the Black Music on Film program that's been assembled by the Black Film Institute at U.D.C.: The Gordon Parks film Leadbelly will be shown at 6:30 on Tuesday, and the rarely seen St. Louis Blues, starring Nat King Cole, Eartha Kitt, Pearl Bailey and Cab Calloway will be shown with a 22- minute docudrama on Cole on Thursday, also at 6:30. Admission is free; all films are shown in Building 41, Room A03 of the school's Van ess campus, 4200 Connecticut Avenue NW. Call 727-2396.

The Mary Pickford Theater begins a new round of screenings Wednesday with Blue Collar Thirties, a three-month collection of films highlighting the American worker. Since the Warner Bros. lot specialized in social commentary (Cagney, Muni and Davis did some of their best work there), most of the titles selected are from that studio, with an emphasis on films produced before Will Hays began enforcing the Production Code. As if that weren't enough for film buffs, the series was also conceived as a showcase for brand new 35mm prints recently struck by the Motion Picture Preservation Laboratory in Dayton. Coming titles include the Roy Del Ruth film Employees' Entrance, with Warren William and Loretta Young (Wednesday at 6:30 and 8:15); Mervyn LeRoy's I Am a Fugitive From a Chain Gang, with Paul Muni (Thursday at 5:30 and 7:30); and a Jean Arthur film called If You Could Only Cook, a 1936 Columbia effort co-starring Herbert Marshall, Leo Carillo and Lionel Stander (July 15 at 7:30).

Also on the agenda at the Pickford is a retrospective of Jason Robards' work, beginning July 22 with an appearance by Robards to discuss his career and preside over a screening of clips from his most memorable films. Because seating is limited to only 64 seats, it's important to remember the reservation policy at the Pickford Theater (in the Library of Congress' James Madison Building, Independence Avenue at First Street SE). Beginning one week before a given show, you can phone in your reservations at 287-5677 during business hours Monday-Friday, 8:30-4:30. You must claim your seat 10 minutes before a screening starts, or it'll be given away to the inevitable standbys. The Robards event will be held in the building's Mumford Room, which seats 200.

Paul Wagner, co-producer of The Stone Carvers (which won this year's Oscar in the Documentary Short category), will lead a seminar on Careers in Independent Filmmaking on July 18 from 7 to 9:30 p.m. Presented under the aegis of Open University, the seminar will feature a screening of "The Stone Carvers" and a description of its genesis and production. It will be held at the Shoreham Hotel, 2500 Calvert Street NW. The cost is $24; advance registration is required; no admissions will be sold at the door. Call 966-9606.

The Gaithersburg branch of the Montgomery County Department of Public Libraries is presenting a weekly series of films keyed around Great Actresses of the Past. Beginning Thursday at 7 and running for seven consecutive weeks after that, the free program opens with Stanley Donen's 1957 Gershwin musical Funny Face, with Audrey Hepburn. The series continues with Debbie Reynolds in Singin' in the Rain (July 18); Marlene Dietrich in Josef von Sternberg's The Blue Angel (July 25); Celia Johnson in the classic weepie Brief Encounter (August 1); Lili, with Leslie Caron (August 8); Joan Fontaine in Hitchcock's Rebecca (August 15); Jane Wyman in The Yearling (August 22); and Rosalind Russell as the ace reporter in Howard Hawks' His Girl Friday (August 29). Call 840-2515.

According to the Washington-based Motion Picture Information Service, the area's top- grossing pictures for the week ending June 27 were, in descending order, Cocoon (showing lots of muscle in its first run at 17 local screens); Rambo: First Blood Part II (losing one screen but holding tough at 20 in week five); The Goonies (ditto in week three); Prizzi's Honor (staying at 14 houses in its second week); Lifeforce (a so-so debut at 19 locations); Fletch (dropping from 19 to 18 screens); A View to a Kill (staying at 20 houses in week five); Return To Oz (opening at 13 theaters to tepid grosses); Brewster's Millions (moving from 19 to 14 screens and dropping a good 35 per cent in per-screen average in its fifth week); and Secret Admirer (remaining at 13 screens but losing a full 38 per cent of its per-screen average in week two).

By the way, if you want to see "Return to Oz" in 70mm at the Uptown, you'll have to catch a matinee; because of poor business, the Circle organization has booked a 70mm print of Apocalpse Now in for the evenings.

PAGES OF FILM HISTORY -- Birthday greetings this date to former first daughter Julie Nixon.

Blowing out candles on Saturday are Andrei Gromyko, Merv Griffin, Janet Leigh, comedian Pat Paulsen, singer/actress Della Reese, character actor Ned Beatty, Burt Ward (Robin to Adam West's Batman in the '60s TV show), Sylvester Stallone and another former first daughter, Susan Ford. The first all-talking film, "Lights of New York," opened at the Strand Theater 57 years ago Saturday.

A very happy birthday Sunday to the dean of science fiction, Robert A. Heinlein and to Vince Edwards (Dr. Ben Casey) and Ringo Starr. And it was 27 years ago Sunday that Eward R. Murrow hosted the final edition of "See It Now."

Eddie Cockrell is a freelance film consultant and teacher. His "Insights on Film" is heard Mondays at 5:30 p.m. on WGMS AM & FM.