A new report from Education Trust-Midwest lays out an “education roadmap” for improving average standardized test scores in Michigan. Before describing the roadmap, however, the report goes to great lengths to criticize state policies that have enabled parents to enroll their children in public charter schools. But its case against charter schooling is weak, and the report ignores the best available evidence on the impact charter schools are having in Michigan.

The report states that “…charter schools often perform below traditional public schools that serve exactly the same kind of students.” The evidence provided for this claim is a chart of the 2012 average proficiency rates in reading and math on the state standardized test of some high-poverty schools in Detroit.

This analysis has two major shortcomings. First, it assumes that these test scores from Detroit charter schools are a fair representation of the performance of all charter schools in the state. There’s no other evidence provided to indicate that this is the case. Second, it does not measure the growth that students (in both charters and conventional schools) may be producing over time. Individual students could be making substantial learning gains in schools reporting low overall average scores.

Oddly, the report makes no mention of a recent study from Stanford University that used a much more sophisticated method to analyze charter school performance in Michigan. It measured the growth that individual students in charter schools made in reading and math over a five-year period and compared the learning gains to those made by these students’ “virtual twins” in nearby conventional schools. It included 273 different charter schools from all around the state, not just those in Detroit.

The results were almost entirely positive for charter schools: students made an average of two additional months’ worth of learning gains in both reading and math compared to their peers in conventional schools. Ironically, the charter schools in Detroit did even better than the state average — posting average annual individual learning gains of about three additional months.

Of course not all charter schools are success stories, but the best evidence indicates that charter schools have had a net positive impact on public education in Michigan. Because of charter schools, more parents are able to choose a school they feel better meets the needs of their children, and on average, students are learning more. This latest report’s criticism of charter schools in Michigan inexplicably ignores this evidence and fails to provide sufficient proof to the contrary. 

Permission to reprint this blog post in whole or in part is hereby granted, provided that the author (or authors) and the Mackinac Center for Public Policy are properly cited.