Mayor Bill de Blasio will overhaul New York City’s highly selective, racially segregated gifted and talented education classes, a sea change for the nation’s largest public school system that may amount to the mayor’s most significant act in the waning months of his tenure. The elementary school gifted and talented program that New York has known for the last several decades will no longer exist for incoming kindergarten students next fall, and within a few years, it will be eliminated completely, city officials told The New York Times. Students who are currently enrolled in gifted classes will become the final cohort in the existing system, which will be replaced by a program that offers accelerated learning to all students in the later years of elementary school. The gradual elimination of the existing program will remove a major component of what many consider to be the city’s two-tiered education system, in which one relatively small, largely white and Asian American group of students gain access to the highest-performing schools, while many Black and Latino children remain in schools that are struggling. Gifted and talented programs are in high demand, largely because they help propel students into selective middle and high schools, effectively putting children on a parallel track from their general education peers. But some parents and researchers argue that the programs worsen segregation and weaken instruction for children who are not in the gifted track. New York, which is more reliant on selective admissions than any other large system in America, is home to one of the most racially segregated school systems in the country. The move represents one of Mr. de Blasio’s most dramatic actions to address that, though it also puts New York more in line with how other cities are approaching their own segregated gifted classes. About 75 percent of the roughly 16,000 students in gifted elementary school classes in New York are white or Asian American. Those groups make up about 25 percent of the overall school system, which serves roughly 1 million students. For years, those students got into kindergarten gifted programs by taking a standardized test. “The era of judging 4-year-olds based on a single test is over,” Mr. de Blasio said in a statement about the replacement program, known as Brilliant NYC. “Brilliant NYC will deliver accelerated instruction for tens of thousands of children, as opposed to a select few,” he said. “Every New York City child deserves to reach their full potential, and this new, equitable model gives them that chance.” Though the mayor has long promised to tackle inequality in city schools, he has faced criticism for not taking more forceful action on desegregation until the end of his mayoralty. His schools chancellor, Meisha Porter, who was appointed this year, has been instrumental in pushing him to fundamentally alter the gifted and talented program, according to people with knowledge of the last several months of intensive negotiations on the issue. The change presents an unwelcome challenge for Mr. de Blasio’s almost certain successor, Eric Adams, the Democratic nominee for mayor, who would have to implement an entirely new gifted education system during his first year in office...