Where to drive in. Here's a clean - cut couple of double-features showing this weekend.

Super 29 Drive-in, West Ox Road, Fairfax. Opens at 6:35, showtime, 7:35. "The Great Train Robbery" followed by "Rocky II." Phone: 830-8929.

Wineland's Hillside, 5210 Marlboro Pike. Opens at 7, cartoon at 7:50. "Hurricane" topped of with "Escape from Alcatraz." Phone: RE6-2166.

A small miracle happened a few weeks ago. Our local drive-in took a break from its usual fare of bloody horror and triple-X ratings to actually begin showing a family-type film -- "Superman."

"You said. so, Mom," the children came running, waving the newspaper. "You said we could go as soon as they had a movie you weren't afraid to see." (The emphasis is on the you -- the children will brave anything, but I was terrified by "Jaws.,)

We packed a picnic dinner of fried chicken, pepperoni slices, stuffed celery, grapes and chocolate-chip cookies and arrived at the drive-in at 7, about an hour before showtime.

"It's going to be so comfortable watching the show in the van," said Jeffrey, happily leaning back on one of the couches. (We recently became the proud owners of a customized van: It's just a little more luzurious than our house.) Jeffrey's enthusiasm dimmed a bit, however, when the manager told us to "park over there in the back with the other trucks."


"Oh well," Jeffrey said philosophically, I can always sit up on top if I can't see." Then again, maybe not: Sitting on the roof, we later learned, is strictly forbidden.

After we parked, Jeffrey and Linda headed over to the playground -- located in a grass - and stone-covered area just below the screen. Children of all ages and sizes swarmed over the monkey bars, swings, see-saws and four huge slides. "These swings are the best in the world," one youngster shrieked. "They go so high."

Younger children navigated the smaller slides and those younger still were being pushed on the baby swings or in carriages and strollers. "I sure hope he falls asleep before the picture starts, "said one father completing his second trip through the park.

A young mother patted her loudly screaming infant on the back. "She'll be fine as soon as she burps," she said. "Burp, baby. It's almost time for the movie and you don't want to bother all the people with your crying."

My husband and I, parents of older children, sat sedately and somewhat smugly on the park benches enjoying the cool breezes after the heat of the day.

"Let's just check out the snack bar," Jeffrey suggested on the walk back to the van. He debated between French fries and popcorn, stared at the Coke machine for a long, thoughtful moment and finally settled on a package of chocolate mints. After equally lengthy deliberation, Linda opted for Tootsie Rolls. They left open the possibility of a second trip later for a hamburger or hot dog -- particularly "if the movie is real long."

We settled down in the van just as the first cartoon flickered onto the screen, and spent the next half hour trying to adjust the sound. Like a lot of drive-ins nowadays, this one doesn't have those clamp-on window speakers anymore. The new improved drive-in allows you to dial the sound on the car radio, which in this case gave us lots of static, interrupted now and then by a few snatches of dialogue. "There must be a storm coming up," said my husband as he fiddled with the dial and the antenna. "Listen to that wind. There -- isn't that lightning?"

Fortunately, the cartoons and "Superman" were longer on action than words and it was delightful to sit in comfort watching the show and munching cold chicken.

"Mom," one of the kids whispered. "I spilled the potato chips."

"Pick them up, every one, and don't tell Dad," I whispered back.

The show, which included three cartoons, a short feature on the Air Force, two previews of coming attractions and a clever commercial for the snack bar, ended at 11:30. ("All that's missing is a newsreel," said my husband.)

When the children were smaller they used to bring along their pillows and pajamas and fall asleep halfway through the movie. When we saw "Gone With the Wind," they completely missed the Burining of Atlanta. Nowadays, however, I'm the one who nods off. I'm told I missed Superman's most spectacular rescue scene.