Executive Summary / Acknowledgements & Disclaimers

How we got here

CREDO, the Center for Research on Education Outcomes at Stanford University, was established to improve empirical evidence about education reform and student performance at the primary and secondary levels. We support education organizations and policymakers in using reliable research and program evaluation to assess the performance of educational research initiatives. Our valuable insight helps educators and policymakers strengthen their focus on the results of innovative programs, curricula, policies and accountability practices.


We gratefully acknowledge the support of the state education agencies that contributed their data to this partnership. Our data access partnerships form the foundation of CREDO’s work, without which studies like this would be impossible. We strive daily to justify the confidence placed in us.

We also acknowledge the Walton Family Foundation and The City Fund for supporting this research.


The educational research presented here uses confidential data from state departments of education. The views expressed herein do not necessarily represent the positions or policies of the organizations noted above. No official endorsement of any product, commodity, service or enterprise mentioned in this publication is intended or should be inferred. In addition:

  • The research presented here utilizes SLDS Data from the Idaho State Board of Education (SBOE) and the Idaho State Department of Education. Any research errors are the sole responsibility of the author(s).
  • This research result used data structured and maintained by the MERI-Michigan Education Data Center (MEDC). MEDC data is modified for analysis purposes using rules governed by MEDC and is not identical to data collected and maintained by the Michigan Department of Education (MDE) and/or Michigan’s Center for Educational Performance and Information (CEPI). Results, information and opinions solely represent the analysis, information and opinions of the author(s) and are not endorsed by, or reflect the views or positions of, grantors, MDE and CEPI or any employee thereof.
  • Data for this report was provided by the Missouri Department of Elementary and Secondary Education.
  • The conclusions of this research do not necessarily reflect the opinions or official position of the Texas Education Agency, the Texas Higher Education Coordinating Board, or the State of Texas.

The analysis and conclusions contained herein are exclusively those of the authors and are not endorsed by any of CREDO’s supporting organizations, their governing boards, or the state governments, state education departments, or school districts that participated in this study. All errors are attributable to the authors.

Explore the written reports

STUDY I – 2009 National
Charter School Study

STUDY II – 2013 National
Charter School Study

STUDY III – 2023 National
Charter School Study