<p>Mackinaw, I think you asked for an example. However, there were more stories buried in the links: </p>
<p>See <a href="http://www.manhattan-institute.org/html/ewp_02.htm%5B/url%5D">http://www.manhattan-institute.org/html/ewp_02.htm</a></p>
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The results demonstrate the following:</p>
<p>Floridas low-performing schools are improving in direct proportion to the challenge they face from voucher competition. These improvements are real, not the result of test gaming, demographic shifts, or the statistical phenomenon of regression to the mean. </p>
<p>Schools already facing competition from vouchers showed the greatest improvements of all five categories of low-performing schools, improving by 9.3 scale score points on the FCAT math test, 10.1 points on the FCAT reading test, and 5.1 percentile points on the Stanford-9 math test relative to Florida public schools that were not in any low-performing category. </p>
<p>Schools threatened with the prospect of vouchers showed the second greatest improvements, making relative gains of 6.7 scale points on the FCAT math test, 8.2 points on the FCAT reading test, and 3.0 percentile points on the Stanford-9 math test. </p>
<p>Low-performing schools that have never received any grade other than a D, or that have received at least one D since FCAT grading began, produced small and indistinguishable gains, respectively, relative to Florida public schools that were not low-performing. While these schools were similar to schools facing voucher competition, they failed to make similar gains in the absence of competitive incentives. </p>
<p>Some researchers theorize that failing schools improve because of the stigma of a failing grade rather than the threat of voucher competition. The results of this study contradict this thesis. Schools that received one F in 1998-99 but none since are no longer exposed to the potential of voucher competition. These schools actually lost ground relative to non-low-performing Florida public schools, supporting the conclusion that once the threat of vouchers goes away, so does the incentive for failing schools to improve.
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<p>Oops, almost forgot. This is an link from an interestingly named Mackinac Center for Public Policy. What is a C when you have a W. :)</p>
<p><a href="http://www.mackinac.org/article.aspx?ID=6840%5B/url%5D">http://www.mackinac.org/article.aspx?ID=6840</a></p>