In their plans to carry out the Every Student Succeeds Act (ESSA), states universally recognize what New Leaders has long known: "leadership changes everything." In fact, every single state has committed to directing some portion of its federal funding into investments in leadership--from teacher leaders to principals and…

Teachers have the greatest school-based effect on the achievement of any child in their classrooms, but highly effective principals can positively affect the achievement of every student in their schools. The difference between a highly effective principal and an average one is equal to two-to-seven months of extra learning per year for each child…