Here's an article Klein published in the WSJ earlier this month:

Over the past eight years, I've been privileged to serve as chancellor of the New York City Department of Education, the nation's largest school district. Working with a mayor who courageously took responsibility for our schools, our department has made significant changes and progress. Along the way, I've learned some important lessons about what works in public education, what doesn't, and what (and who) are the biggest obstacles to the transformative changes we still need.

First, it is wrong to assert that students' poverty and family circumstances severely limit their educational potential. It's now proven that a child who does poorly with one teacher could have done very well with another. Take Harlem Success Academy, a charter school with all minority, mostly high-poverty students admitted by lottery. It performs as well as our gifted and talented schools that admit kids based solely on demanding tests. We also have many new small high schools that replaced large failing ones, and are now getting outsized results for poor children.

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