Chicago’s Best Public Schools
For our new rankings of the Chicago area’s public elementary and high schools, we plunged deeper into the data than ever before, using smarter, fairer, and more reliable new ways of measuring performance—and got some surprising results.
The way we assess school quality is changing fast. When Chicago last ranked public schools, in 2012, we followed standard practice at the time and threw a lot of weight on test scores. For one thing, they were a widely available and consistently reported measure of performance. For another, standardized test results—typically expressed as a percentage of students who meet or exceed state standards on a given exam—offered nice, clean, ostensibly meaningful numbers that could be compared at a glance.
But as any teacher or principal will tell you, test scores aren’t everything. They may be useful for showing academic achievement at a single point in time, but they don’t show gains or losses over the duration of students’ tenure. And with Chicago’s disparate student population, that can be a big limitation, because students in poor neighborhoods tend to enter the system at lower levels than students in well-off neighborhoods or those who test into selective enrollment institutions.
What’s more, there’s a growing consensus that single-point-in-time tests aren’t as predictive of future success as once thought. Tim Knowles, the chairman of the University of Chicago’s Urban Education Institute, which contains one of the largest bodies of research on public school assessment in the country, sums it up this way: “What the standardized test score best predicts is how you’ll do on your next standardized test.”
Then there’s the question of how to measure hard-to-quantify factors for which test results can give only a vague indication, such as classroom environment, teacher-principal collaboration, and parent engagement—to say nothing of trying to determine long-term outcomes like college completion or career success.
It all makes for a complicated picture, especially in a time of ongoing fiscal crisis, when there seem to be ever more obstacles to improving public school performance.
The good news? Today there are more and better tools than ever to take the fullest possible measure of a school’s health. For this year’s public school rankings, which cover the city, the rest of Cook County, and five suburban counties, we talked to top professionals and educators inside and outside the school system, researched a wide array of new and improved metrics, drilled down deeper on the numbers, and asked the independent research nonprofit RTI International to crunch the data to generate the fairest possible results.
The outcome was striking in some cases, no more so than with Chicago elementary schools: In our 2012 rankings, 10 of the top 15 slots were filled by selective enrollment schools—ones that students must test into and that admit only a fraction of applicants; in this year’s rankings, only four of the top 15 were selective enrollment.
This underscores the fact that placing more emphasis on factors like academic growth and classroom environment can paint a very different picture of school performance. This year’s rankings honor a wide variety of schools that do a great job of educating, not just those that benefit from a large population of already-high-achieving students.
It has to be said that, given all the variables at play, there is no perfect way to measure a school’s performance. But the best research in the field increasingly points to a few consistent truths. First and foremost, straight test scores must be balanced against academic gains over time. As Elaine Allensworth, a colleague of Knowles at U. of C. and one of the country’s top researchers on school assessment, puts it: “How much students are growing year to year—that’s a much fairer [evaluation] than just judging by average test scores, given that students come in with such different skills.”
The city of Chicago has made strides in tracking academic growth in its public schools. Five years ago, it began reporting year-over-year change on the NWEA math and reading tests that are given to students in elementary schools, as it had been doing with ACT results since the mid-2000s. In our rankings for CPS schools, we gave more weight to these growth metrics than to the straight results for the ACT and for the PARCC exam, which started in 2015 and is the Common Core test administered to all Illinois public school students. (In July, the state declared that starting with the 2016–17 school year, it would no longer administer the PARCC exam to high schoolers.)
Assessing student improvement on standardized tests gets more complicated in the absence of growth data. As of the 2014–15 school year—the most recent for which full data were available when we assembled our rankings—figures for year-over-year changes in PARCC and ACT scores weren’t available for most public schools outside Chicago. So with suburban schools, we compensated for the lack of growth indices with a widely accepted, if imperfect, workaround: We adjusted PARCC and ACT scores for economic disadvantage by factoring in the percentage of low-income students at each school.
One sign of enlightenment in school assessment in Illinois is the statewide adoption in 2012 of a program known as 5Essentials. Developed by U. of C. researchers in conjunction with Chicago area public schools, 5Essentials is a system of rubrics designed to gauge the overall institutional health of a school: specifically, effective leadership, teacher commitment and collaboration, parent and family involvement, classroom environment, and quality of instruction. Results are compiled from teacher and student surveys and are expressed on a 1-to-5 scale.
Though the self-reporting can occasionally pose problems—there is always the potential for survey takers to be less than honest in order to burnish their school’s image—the program has been widely acclaimed by both teachers and administrators as a success. “Some principals try to game the 5Essentials,” says Bill Gerstein, a former CPS principal and teacher, “but it is really very effective in determining whether a school is well run.” A study by the University of Chicago Consortium on School Research showed that schools strong on at least three of the five “essentials” are 10 times more likely to bolster students’ academic achievement than schools that show weak performance on all the rubrics.
This is not to say that old-fashioned indicators like graduation rate and attendance are no longer considered important. Experts see attendance—a metric not even included in our 2012 rankings—as an indicator of how well a school engages its students. The best schools work actively with parents to ensure students limit absences. “Attendance drives everything,” says Allensworth. “If you’re not in school, you can’t learn. High absence makes it harder for teachers to move forward in their lessons.”
Graduation rate also remains a worthwhile metric, though it’s always been a troublesome “lag indicator,” as it measures an outcome for students who entered school four years earlier. (It’s also occasionally been subject to inflation, most recently in 2015, when it was determined that CPS had misreported graduation rates for the previous four years.)
To compensate for this, Illinois recently started publishing a stat called Freshmen on Track, which shows the percentage of ninth-grade students meeting basic academic standards after their first high school year. This metric, which we’ve factored into our rankings, is based on a research-proven premise: A high schooler’s prospects for graduating are largely determined in the ninth grade. In fact, freshmen who are “on track” are four times more likely to graduate than peers who aren’t. Intensified focus on ninth-grade on-track performance in Chicago’s public schools has been credited with significant improvements in graduation rates across the city over the past eight years.
There is still plenty of progress to be made. Full statewide data on long-term attainment indicators, like college admission and (just as important) completion, are not yet available, and many researchers and educators will tell you that there’s still an overreliance on test scores as a stand-in for measures of instruction quality, teacher motivation, and other on-the-ground factors. Even so, parents can be better equipped than ever to do their homework before choosing a school.