The new Charlotte-Mecklenburg school progress reports have helped me to better understand North Carolina's formula for academic growth -- and I'm a bit taken aback.
The state's "expected growth" calculation is key to state ratings and other measures CMS uses to gauge how well its schools and officials are performing. It has been explained to me as roughly translating to an average of a year's academic gain per student, based on their performance on state exams (read the state's description on pages 4-5 here).
So I was looking at West Charlotte High's progress report and scratching my head. If, as the CMS document reports, only 64 percent of last year's students demonstrated at least one year's progress, why did the school get a "high growth" rating?
The answer lies in CMS's explanation, the clearest one I've seen yet: "Each student is expected to perform as well (or better) on the End-of-Course assessment as he or she did, on average, during the previous two years. Average Growth for a school is calculated by comparing actual performance to expected performance and then averaging the difference across all students and all subjects. ... Across the state, about half of students typically meet or exceed this growth expectation. To earn the high growth designation, a school must meet the average-growth standard described above and also have more than 60% of its students make expected growth."
So a student who has performed poorly in the past will go in with a relatively low projected performance. And up to 40 percent of students at any given school can fall even further behind, making less than the gains expected based on their past performance, while the school still gets a "high growth" rating. That helps explain why CMS and the state have so many "high growth" schools (just over 81 percent statewide met or exceeded the growth standard last year) while proficiency levels remain persistently low at some of those same schools.
It's also worth noting that Ardrey Kell and Providence high schools, two of CMS' top performers, had 65 percent of students making the expected gains last year, a number barely above West Charlotte's. In cases like that, a significant number of strong students who have little trouble clearing the "grade level" bar on exams are still falling short on the progress they're expected to make. Districtwide, about 40 percent of students logged less than a year's gains.
Kudos to CMS for including a measure that gives a clearer picture of what lies behind the averages -- and how many students are continuing to fall behind. The real challenge, of course, lies in figuring out what to do about it.