While the overall story of charter school performance is positive, averages hide a lot of variation. There are substantial differences between different schools’ performance.
There are noteworthy differences among states, cities, networks of schools and individual schools. Some are providing students with high-quality choices and helping them to excel academically — while others are not helping students to accelerate their learning.
Center for Research on Education Outcomes: Urban Charter School Study: Report on 41 Regions, 2015. Days of learning conversion on page 5.