A recent policy brief has examined how charter schools compare to traditional public schools in terms of student growth and the closing of the achievement gap, and findings from suggest that charter schools are doing better in these areas than their public school counterparts.
Growth and Gaps, released by the Wisconsin Institute for Law and Liberty, looked at data to evaluate the success of different types of charter schools in comparison to public schools throughout Wisconsin regarding academic growth and the closing of the achievement gap.
The study found that independent charter schools scored higher on all student growth and achievement gap measures than traditional public schools did. On average, these schools scored 5.9 points higher on the School Report Card's student growth measures when compared to the average score received by public schools in the state. In addition, the charter schools were found to score on average 12.5 points higher on closing the achievement gap in comparison to traditional public schools. On closing graduation rate gaps, independent charter schools were found to score an average of 9.7 points higher.
The authors suggest that this is due to the focus of independent charter schools on their missions and the disadvantaged students within their walls. Charter schools are offered greater autonomy and freedom that public schools within the same district do not receive, which allows them the opportunity to experiment with their teaching methods.
Public charter schools were found to have higher scores on all student growth measures. Non-instrumentality charter schools were found to score around 6.1 points higher than traditional public schools, and instrumentality charter schools scored around 3.8 points higher. No difference was found concerning achievement gap scores when compared to traditional public schools.
Virtual charter schools were also found to have scored higher for student growth, specifically concerning reading, scoring 0.7 to 1.6 points higher when compared to traditional public schools. While the scores are smaller than those found concerning the other types of charter schools, they are still significant because they provide evidence that these schools are more effective at closing achievement gaps than public schools.
The authors suggest that the results are even more impressive given the unequal funding situation within Wisconsin's education system. The average per-student funding in the state is $11,720. While public schools in the state receive around $11,282, independent charter schools took in only $7,925 per student in the same time span.
"The implications of our study are clear: Wisconsin needs more public independent charter schools. Yet, state laws severely limit the number of charter authorizers to only a few and significantly restricts independent charter schools from expanding outside of Milwaukee. School districts do most of the authorization, and, consequently, the vast majority of "charter" schools are simply extensions of the traditional public school system."