When asked about school segregation in New York City, Mayor Bill de Blasio has said that schools are segregated because neighborhoods are: “We cannot change the basic reality of housing in New York City.”

Now, as a debate about plans to integrate middle schools has engulfed one Manhattan district, a study being released on Wednesday undermines that notion. It found that a full 40 percent of New York City kindergartners do not attend the nearby school to which they are assigned. That’s a vast stream of 27,000 5-year-olds funneling through the city each day.

Read more in The New York Times.