The Chicago choice system works exactly as every choice system works: It segregates students by ability.

“But a new WBEZ analysis shows an unintended consequence of the choice system: students of different achievement levels are being sorted into separate high schools.

“WBEZ analyzed incoming test scores for freshmen from the fall of 2012, the most recent year data is available. That year, the district mandated that every high school give students an “EXPLORE” exam about a month into the school year.

“The 26,340 scores range from painfully low to perfect.

“WBEZ found few schools in the city enroll the full span of students. Instead, low-scoring students and high-scoring students in particular are attending completely different high schools. Other schools enroll a glut of average kids.”

And more:

“The findings raise some of the same long-running questions educators have debated about the academic and social implications of in-school tracking. But they also raise questions about whether the city’s school choice system is actually creating better schools, or whether it’s simply sorting certain students out and leaving the weakest learners in separate, struggling schools.

WBEZ’s analysis shows:

Serious brain drain. The city’s selective “test-in” high schools — among the best in the state — capture nearly all the top students in the school system. There were 104 kids who scored a perfect 25 on the EXPLORE exam. One hundred of them — 96 percent — enrolled in just six of the city’s 130 high schools (Northside, Whitney Young, Payton, Lane, Lincoln Park, and Jones). In fact, 80 percent of perfect scorers went to just three schools. Among the city’s top 2 percent of test takers (those scoring a 23, 24, or 25 on their exam), 87 percent are at those same six schools. Chicago has proposed creating an 11th selective enrollment high school, Barack Obama College Prep, to be located in the same area as the schools already attracting the city’s top performers.

“Clustering of low-performing students. Fifteen percent of the city’s high schools are populated with vastly disproportionate numbers of low-performing students. More than 80 percent of incoming students at these schools score below the district average. The schools enroll 10 percent of all Chicago high school students.
Black students are most likely to be affected by sorting. WBEZ’s analysis shows African American students are doubly segregated, first by race, then by achievement. Of the 40 most academically narrow schools in Chicago, 34 of them are predominantly black. Even though just 40 percent of students in the public schools are African American, Chicago has black high schools for low achievers, black high schools for average kids, black test-in high schools for high achievers.
Within neighborhoods, more sorting. Schools within a particular community may appear to be attracting the same students demographically, but WBEZ finds significant sorting by achievement. Especially in neighborhoods on the South and West sides, the comprehensive neighborhood high school has become a repository for low performers; nearby charters or other new schools are attracting far greater percentages of above-average kids.”

Some reform.