School nurse Gloria Hackman's day usually begins as soon as she parks her car outside Maury Elementary School in Northeast Washington. The principal might run up to tell her about students who hurt themselves playing before class. Or she might make it to her office without interruption, only to find a line of children waiting with scrapes or scratches or bellyaches.

"I'll see 16 to 20 children each day with everything from injuries on the playground to headaches and stomachaches. Some of them just want to come in and talk," she said. "Sometimes I don't even have time to take my coat off."

But yesterday was different. President Clinton dropped in for a short visit and listened as Hackman, 47, talked about the most common ailment among the children she cares for: asthma.

Hackman, a District native who has been a nurse for nearly 20 years, began working in D.C. elementary schools two years ago. She was immediately struck by the number of children who are asthma sufferers. Of the 315 students at Maury, about 25 have been diagnosed with the condition--one of the highest rates in the city's public schools.

"They'll come in every day, coughing or wheezing, especially in the wintertime," she said. "I think the pollution in the air has a lot to do with it. You've just got more and more cars on the road."

So Hackman was particularly pleased to introduce Clinton to the audience in her school's gymnasium and to hear him formally announce plans to tighten emissions standards for cars, impose the same standards on sport-utility vehicles and require oil companies to produce cleaner gasolines.

On Friday, a White House staff member called Hackman out of nowhere and asked her to prepare a speech for the president's visit. It wasn't much notice, she thought, but who was she to decline? She worked on it over the next few days.

Hackman arrived at school yesterday morning with a sore throat and butterflies in her stomach. Moments before Clinton arrived, she gargled water to soothe her throat. There was little she could do to soothe her nerves. "It's not every day that you meet the president," she said.

But when she stepped up to the microphone, the president seated just behind her, Hackman delivered her speech without a hitch. She told the audience how more than 5 million children across the country suffer from asthma. And she told those gathered that it is the leading cause of school absenteeism.

"I see the difficulties children with asthma face, from having to remember to use their inhalers to reducing their outdoor activities on days with poor air quality," she said. "As a school nurse, my goal is to keep children in the classroom, because a child who is having difficulty breathing cannot focus on school lessons."

Hackman also described the "Open Airways" class she teaches once a week for children with asthma. It's designed to help students learn to manage the illness better and take steps to prevent attacks.

She and 12 other school nurses in the District--most of them in Ward 6, which has the highest incidence of pediatric asthma in the city--were trained this year to teach the classes by the American Lung Association and the U.S. Environmental Protection Agency. Similar classes are held in 18,000 schools nationwide, reaching 200,000 children, officials said.

When Hackman finished speaking, Clinton stepped up, gave her a big hug and whispered, "Good job, Mrs. Hackman." He then turned to the audience and said: "I want to thank Gloria Hackman for the fine statement she made and for her 20 years of dedication as a nurse. As the son and grandson of nurses, I liked hearing her speak."

Hackman sat there, beaming.

Later, recalling the moment in her little office after the reporters and Secret Service agents had left, she said, "It made me feel great, like I was part of history and helping the children of our future."

CAPTION: Gloria Hackman, the nurse at Maury Elementary School in Northeast Washington, applauds with President Clinton as speakers discuss the new vehicle emissions standards.

CAPTION: President Clinton poses with students at Maury Elementary School after unveiling tougher vehicle emissions standards. He was introduced by nurse Gloria Hackman, who spoke about childhood asthma.