One of the country's most prestigious education prizes was awarded Tuesday to the Miami-Dade County Public Schools for improving student achievement, raising the graduation rates of minority students, and increasing the percentage of minorities reaching advanced levels on state exams.

Miami-Dade, the country's fourth-largest school district, had been a finalist for the Broad Prize for Urban Education five times before winning the honor this year. National education officials announced the award at The Museum of Modern Art in New York.

"To give every child a fair shot at the American dream, big-city school systems must deliver an education that prepares young people for college and careers," U.S. Education Secretary Arne Duncan said. "I commend the entire Miami-Dade community for establishing a district-wide culture of results that empowers teachers and students, puts more resources into helping children in the lowest-performing schools, and is helping narrow the achievement gap."

Miami-Dade will receive $550,000 in scholarships for students who demonstrate financial need and academic improvement. Three school districts were chosen as finalists and will receive $150,000 each: the Palm Beach, Fla., district; the Corona-Norco district in Riverside County, Calif.; and the Houston public schools.

Miami-Dade County Public Schools includes the city of Miami and enroll nearly 350,000 students. Ninety percent of the district's students are black or Hispanic and for 21 percent, English is not their primary language. Seventy-four percent are eligible for free or reduced-price lunches, a key indicator of poverty.

Rudy Crew, former chancellor of the New York City schools, led the district from 2004-2008, followed by the current superintendent, Alberto Carvalho.

In announcing the prize, education officials commended Miami-Dade for outperforming other peer districts in Florida at all school levels in math, reading and science.

It was also praised for the academic achievement of its minority students: The district ranked in the top 30 percent in the state in terms of increasing the percentage of black students performing at the highest achievement levels in elementary and high school math, reading and science, as well as the percentage of Hispanic students scoring at the top achievement levels in state exams.

The Broad Foundation noted Miami-Dade has succeeded in raising graduation rates for Hispanic and black students at a faster pace than other large urban districts across the country. From 2006 to 2009, each group saw a 14 percent increase — to 57 percent for black students and 68 percent for Hispanic students.

The district has instituted a number of reforms in recent years, including using student achievement data to guide decisions about the best way to teach students and in which areas to focus.

Within the past year, the district has also put in place a merit pay program for teachers and changed the way instructors are evaluated.

"What is encouraging about Miami-Dade is its sustainable improvement over time," said Eli Broad, founder of the foundation that awards the prize.

He credited the district's hardworking teachers, administrators and parents.

"There is still a long way to go before all American students graduate with the skills and knowledge they need to thrive in a global economy, but Miami-Dade's progress serves as an example for other urban districts across the country," Broad said.