Amid the flash of razzle-dazzle marching bands, the heart of yesterday's 50th annual School Safety Patrol Parade were the children adorned in simmering colors, plumes and fringe--ordinary children far from ordinary for a day.

Thousands of them high stepped along Constitution Avenue from Seventh Street to 17th Street, marching for safety and community pride in a tribute to the work of those who stand on street corners near Washington schoolhouses, their arms outstretched and fluorescent belts draped over their shoulders.

It is a once-a-year chance for the safety cadets to walk down the middle of one of the widest streets in the nation's capital, pumped up with pride, reveling in their sense of responsibility and hoping a turn here or a clever chant there will bring their school recognition.

It was a chance for schools like Washington Highlands Community School in often maligned far Southeast Washington, last year's grand-prize winners, to snatch a little glory--though the winners of yesterday's competition won't be announced until tomorrow.

Yesterday was a big day for little children. Disneyland stars Mickey Mouse and Minnie Mouse were the grand marshals. D.C. Police Chief Maurice T. Turner was there, a public safety professional honoring his junior colleagues. And there was Mayor Marion Barry, waving from atop a marble-white Mercedes-Benz convertible. City Council member David A. Clarke, peddled a bicycle close behind.

Under cloud-spotted skies and in temperatures hovering in the upper 70s, some of the parade's 10,000 participants held their miniature bodies taut, eyes ahead, and struggled to conform to the uniformity of the group. Left, right, left was the order of the day.

Others, supercharged with preteen energy, leaped in fast-footed, hip-dipping routines that drew cheers, giggles and applause from a crowd craning its collective neck to see yet more. D.C. Park Police estimated that more than 25,000 people attended the parade, which included participants from 185 schools in the city.

Kimberely Douglas, a fifth grader at Syphax Elementary School in Southwest Washington, said she was thinking of only one thing--a trophy. "I came here to march and win," she said.

Win or lose, yesterday's procession capped days, weeks and in some instances months of preparation throughout the city.

Earlier last week, Douglas and her classmates marched down Carrollsburg Place SW in final rehearsal. In another part of town, Buckai Ahmad, captain of Immaculate Conception School's 25-member team, tried to pack away his shyness and polish the marching skills of his team, which represents a small parish school in the Shaw neighborhood in Northwest Washington.

"Ah-ten-shun," Buckai commanded his charges, who grew rigid at the words. "We practice hard," said the 12-year-old who prefers paperback novels to basketball. "When you are the captain, you have to make sure they stay on the right foot and the lines stay straight." He said he's learned from his tasks that he can be dependable with a large group.

Sister Frieda, the school's principal, watched from the school's steps and smiled as tiny sneakers and sandals softly patted the pavement in time. She, too, looked forward to yesterday's parade, she said.

"We're aiming to win some kind of prize this year," she said, still watching her children, who were now stomping their feet and slapping their thighs doing something they called "The Ultimate."

Last year, Washington Highlands Community School won it all: first place among schools from the 7th Police District, first place among all schools in the District of Columbia.

The school is a rambling corral of bricks surrounded by housing projects, street life and poverty. It's a place where school principal Shirley Mitchell said children read a lot of negative things about their community. It's a place where she works to improve her students' self image.

Friday, African dress-up day at the school, the school's contingent of 85-strong practiced for almost two hours, at first on the blond floor of the school's gymnasium and then on dusty Eighth Street SE.

Estella White came to see her children, Tabitha, 11, and Victor, 12, work the bugs out of their routine. White's mother, Elnora Debro, 70, took a 25-minute bus ride to the school to oversee all three.

White brimmed with pride when she talked about her children and their part in the parade. "Last year, when they won, Tabitha was a pompon girl. This year she is a safety patrol," she said. "I'm going to keep my fingers crossed."

Yesterday, the sturdy old grandmother stood by the children, all her children this day, dressed in a red-and-white Washington Highlands T-shirt and baggy white slacks.

Though their section of the parade was yet to step off, a winning spirit moved through the excited bunch of children like a smoothing summer breeze as they practiced their moves on the Mall.

"I'm not going to march all the way with them," Debro said, from under a white beaded tam. "I'm gonna walk a ways with 'em." Then, like the others, she would wait until tomorrow.