In the never-ending debate on test scores in Milwaukee’s Parental Choice Program, old is new again. Alan Borsuk, in his most recent column discussing the topic, brings up the possibility that higher scores in choice schools might be the result of better parents and students taking advantage of the program, leaving the worse students behind for MPS to deal with. This is notion of “creaming” is pervasive among opponents of school choice. But the evidence does not support it.
First, by all of the measures that are able to be observed, it is worth noting that students in the MPCP and MPS are very similar. Demographic data for choice students was not included in the DPI release for this year, but the 2017-18 numbers reveal 77.5% of students in the MPCP come from low-income backgrounds compared to 84.8% in MPS. 87.3% of MPCP students come from minority backgrounds, as do 89.3% of students in MPS. There are no significant differences along these dimensions. When WILL conducts it’s annual Apples to Apples report that accounts for demographic factors like these, choice schools still rise to the top.
But what Borsuk is probably really focused on are more intangible differences between the students. If a parent takes the time to seek out an alternative educational option, it may indicate some additional level of caring about a child’s education than a parent who leaves their child in an assigned school, whatever its quality. Fortunately, there are a number of studies that are also able to account for this possibility thanks to lotteries that were held to determine admissions to the school. Such research takes advantage of random assignment to receiving school choice, usually due to limitations in the number of vouchers that are available. This means that the students who lose the lottery come from the same sort of family environments as those that win the lottery, allowing for a true effect of educational choice to be observed experimentally. Of 18 studies that have used these methods, 14 have found positive effects on student achievement, 2 have found no effects, and 2–both in Louisiana–have found negative effects. This includes 2 studies in Milwaukee conducted before caps were lifted on the program. In other words, the vast majority of studies that directly address Borsuk’s worry have found no evidence of the problem.
Perhaps the reason for this is that it isn’t just the “cream of the crop” that make the decision to send their students to an alternative school. Indeed, a case can be made that if a student is doing very well in their current public school, why would a change be needed? Of 10 studies that have examined this very question, eight find either evidence in the opposite direction or ambiguous results, and only two find choice students are more advantaged.