"Twenty years later, there is no comprehensive index of national charter school rankings. Without them, it's hard to compare schools across state lines, especially because of differences in standardized tests. The closest thing to an answer is a trove of studies from Stanford University's CREDO center.... In Michigan, the evidence on charter school quality is clearer. Students in charter schools there perform worse on average than public school students, according to a 2007 study by Gary Miron, a professor at Western Michigan University... A CREDO study on Michigan released this week found that 80 percent of charters perform below the 50th percentile of achievement in reading, and 84 percent perform below that threshold in math."
Also, "according to the National Association of Charter School Authorizers, 26 percent of Michigan charter schools fall into the bottom 15 percent of the state |