Success Academy Charter Schools, New York City’s largest network of free charter schools, has recently been the center of controversy over its policies on student behavior. Our critics accuse us of pushing out children who might pull down our test scores, and in doing so creating what some call “a kindergarten-to-prison pipeline.” In reality, our attrition rates are lower than those of the district schools. How then do our students, chosen by lottery and mainly children of color, routinely outperform even students from wealthy…