Last June, John and Edith Kuhnle moved into their new house at the corner of 34th and Newark Streets NW. The first thing they did was to sit their two young daughters on the front steps and give them a lecture.

"We told them that whenever they came down the steps, they should forget about even looking to the left, toward 34th Street," Edith Kuhnle said. "We didn't want them even thinking about crossing."

Four years earlier, Joe and Carol Bosco moved from their home near 34th and Rodman streets NW to a similar one only eight blocks away. The majority reason: so their three children could live on the same side of 34th Street as the school they attended.

"Every morning they don't have to cross that street, I feel better," Carol Bosco said.

At Johanna Anderson's home on the corner of Reno Road and Fessenden Street NW, the air conditioners run most of the year -- to drown out traffic noise.

At Reno and Military roads NW, Herb Reff refuses to let his three children play in the front yard because of auto exhaust fumes.

At Reno Road and Van Ness Street NEW, Esther Foer has never welcomed a guest at her front door because the only parking is behind her house.

Once a tranquil, tree-lined lane through the hills of Cleveland Park, Reno Road has become Washington's biggest traffic battleground.

Over the last five years, a three-mile-long corridor including stretches of 34th Street, Reno Road and 41st Street, has been the focus of demonstrations, petition drives and letter-writing campaigns.

Last November, there was even a dab of guerrilla warfare -- a caravan of neighborhood residents spent the day driving up and down the corridor at the maddening -- but legal -- school zone speed of 15 miles an hour. In most of the corridor, the speed limit is 25 miles an hour.

The idea was to make Maryland commuters, who constitute 70 percent of Reno Road's traffic, aware of the speed limits. . The effect, notes Herb Reff, president of the Reno Road Corridor Coalition, "was to make them damn made."

That would hardly be a first in the Reno Road dispute, in which much of the anger of corridor residents has been directed at the D.C. Department of Transportation.

Although DOT has pledged to take steps to reduce traffic in the corridor so that it can again have a "residential character," Reff charges that the agency is dragging its feet.

"They're stalling," he said. "They're hoping that the extension of Metro to Shady Grove in 1983 will remove enough commuter traffic that they won't have to do what we want.

"But, listen, this is the Northwest Freeway. And DOT could change that tomorrow if they wanted. But they don't."

Meanwhile, although Metropolitan Police say they spend two hours a day running radar speed traps on the corridor, residents think much more could be done.

"All we ask is that they enforce the law vigorously, which they don't," said Joe Bosco.Even Deloris Clark, the crossing guard for John Eaton Elementary School at 34th and Lowell streets NW, thinks that "we need some officers up here. They're speeding on this street, believe me."

Still, the Reno Road corridor has already gottencontinual attention from DOT. In fact, with its reversible rush-hour lanes, its four different parking policies and its 447 traffic signs, Reno Road may be the most tinker-with street in the city.

Even so, it underwent further tinkering Sept. 2. Special 15-mile-an-hour speed zones were established in front of the two public elementary schools -- Eaton and Murch -- that front on the corridor.

And more tinkering is on the way. According to George Jivatode, chief of DOT's technical division, the following additional steps will be taken in the Reno Road corridor and should be completed by next spring:

Within the next month, signals at seven intersections will be converted to flashing red in all four directions between 7 p.m. and 6 a.m. "The idea is to break up the thought of Reno as a continuous thoroughfare," Jivatode said. Livingston, Albemarle, Van Ness, Tilden, Porter and Garfield streets and Woodley Road will be affected by the changes.

The entire corridor will be converted to one lane of traffic in each direction at all times. At present, about half the corridor has two lanes in each direction. The other half has two lanes in one direction and one in the other -- but the direction of the middle lane shifts according to the time of day. In addition, parking will be permitted along some sections of the corridor for the first time.

A special system banning certain right turns will be instituted to discourage motorists coming south on Wisconsin Avenue from cutting over to Reno. Right turns will be banned from Livingston onto 41st, from Military Road onto Reno and from Fessenden onto Reno.

Together, the three steps will reduce peak loads in the corridor by about 600 cars per hour, Jivatode said. The steps cannot be taken right away "because we have to have some place to put the cars we displace," he said. DOT is considering eliminating some parking along Wisconsin Avenue for that purpose, he said.

Sgt. James St. John, acting commander of the second police district, acknowledged that "the Reno Road problem is real." However, he said, police "already give more attention to Reno Road than to any other traffic problem in the district. It's because of all the people calling all the time, all the publicity. The wheel that squeaks is the one that gets the attention."

St. John said that enforcing speed limits with radar "puts out of service one of the six scout cars that patrols the whole district. I had a 47.3 percent increase in burglaries in this district since Jan. 1. What do you want me to do? We have priorities.

"We're not detailing somebody up there all day every day. We never have and I doubt we ever will."

St. John noted that pulling over a speeder on Reno Road's often-narrow lanes can pose as much of a hazard as the speeder. Besides, St. John pointed out, no intersection on the corridor has ever cracked the city's annual list of Ten Most Frequent Accident Sites.

According to police statistics, there were 65 accidents in the Reno Road corridor between Jan. 1 and Aug. 31 this year, up from 34 during the same months of 1979. The corner of Reno and Van Ness accounted for 12 of the 1980 total. The last traffic fatality in the corridor occurred in 1978.

Traffic along the Reno Road corridor has affected social life in a subtle, yet discernible, way.

For example, Carla Bosco, 9, would like to play after school with several school friends who live on the other side of 34th Street. But because her mother insists on walking with her when Carla crosses 34th, "it often becomes a hassle, and we often don't bother," Carol Bosco said.

Meanwhile, every summer, Joe Bosco helps organize a neighborhood bus trip to Baltimore for an Orioles baseball game. A wide range of Cleveland Parkers used to go. But when the bus pulled away two weeks ago, "everyone on it lived on this side of Reno Road," Bosco said.

Real estate sales have been profoundly affected by the traffic, too, according to Jeanne Livingston, an agent who has specialized in the area for the last nine years.

Houses fronting on the corridor can take as long as five months to sell, Livingston said. The Cleveland Park average is 20 days. In addition, a comparable home on a quieter street will sell for at least 10 percent more, Livingston said.

Herb Reff and many members of his coalition admit that they have thought about giving up and moving.

"But living on Reno Road is a personal thing for me," Reff said. "We had our wedding reception at the same house we live in. It means something to us.

"But all this street means to most people who use it is a way to get to work. Fast.

"We're not saying close the street. We're saying 'return it to the residential character it used to have -- while it still has some residential character.'"