More About Attrition Rates in Boston Charter Schools
The debate over Massachusetts's Question 2 -- a referendum on lifting the cap on the number of charter schools in the commonwealth -- rages on. When I last weighed in, I pointed out that the "successes" of Boston's charter sector could not fairly be compared to the "failures" of the public schools because the two sectors were educating fundamentally different students.
One indicator of this is the cohort attrition rate: the shrinkage in the size of a cohort that occurs because students leave a school, but are not replaced with new students entering.
Here's a school that "backfills"; in other words, as students leave because their families move, or they drop out, or they transfer, or whatever, they are replaced by new students entering the system.
This school doesn't backfill. What happens to the size of their cohorts (another way of Jersey Jazzman: More About Attrition Rates in Boston Charter Schools:
