The District of Columbia’s public charters very infrequently enroll students midyear in their schools, even when there are vacancies, a new analysis finds.
In a study of D.C. school data, the authors found little evidence that the city’s charter schools are systematically “pushing out” students midyear—an argument often made by charter school critics. But they are far less likely than most of the city’s other public schools to enroll students midyear, the authors conclude in the report released earlier this week.
Charters in the nation’s capital enroll some 43,000 students—about 47 percent of total public school enrollment. Though generally supportive of charter schools, the left-leaning think tank’s report takes a tough-love approach to the topic of midyear enrollment, often called “backfill.”
“We think charters have been and can be a way to increase the number of really good seats available to public school students. And if those seats are there, we think they should be filled,” said CAP’s Neil Campbell, who co-wrote the report with Abby Quirk. “We’d love to see more kids have access to them.”
Despite representing a small proportion of overall school enrollment in the United States, charters have assumed an outsize role in the national discourse on education reform. Alongside teacher pay and school segregation, they are among the education issues that Democratic presidential hopefuls have been talking about.
Wait! What’s charter school backfill, anyway?
The basic issue in the CAP report has to do with which students charters are serving, and how that affects school comparisons.
Backfilling just means enrolling students midyear if there are available slots, as there often are if other students leave school during the year. That practice is the norm in noncharter, district-run public schools, which must accept students year round. Depending on state and local rules, charters are not always required to backfill.
That brings up a few different issues. For one, it means fewer students are served in charters that don’t backfill. It also throws school-by-school test-score comparisons off, since presumably the students who stay in charter schools are experiencing fewer disruptions and less mobility outside of school, and are more ready to learn.
There’s an equity issue for the traditional public schools, too. If new D.C. arrivals can’t enroll in charters, the schools they land in are likely to have higher concentrations of mobile students. And research suggests that highly mobile students tend to score lower on standardized tests than their peers.
That’s the perspective that the CAP authors are coming from.
“The negative impacts of that mobility can impact achievement of classrooms in schools enrolling new students—and the concentration of all those kids in one place makes that effect more pronounced,” Campbell said.
(Want more on the charter backfill argument? Arianna Prothero wrote a nice explainer for Education Week a few years back, and Chalkbeat’s Matt Barnum surveys the state of research on charter backfilling.)
The argument over fairness hasn’t been accepted in all quarters: Charters often have strong norms and cultures that are disrupted if not all students are inculcated in them from the beginning of the year, some advocates argue.
Magnets, selective schools also backfill less
Using month-by-month data published by the city, CAP found some interesting patterns in entry and exit rates. First, on average, the city’s charters didn’t have higher exit rates in November than other public schools—though breaking this data down by quartile shows that some charters do have higher rates than others, while the city’s traditional public schools have more consistent exit rates.
Second, they looked at rates of new enrollments in May. Here, the entry rate in traditional public schools, at 7.6 percent, was much higher than in charters, at 0.8 percent.
The phenomenon isn’t just limited to charters, though. The authors also found that the city’s popular magnet and application schools—basically, those schools that don’t have a boundary assignment—had similarly low rates of midyear enrollment.
There’s evidence that the schools do fill any vacancies at the beginning of the following school year. Looking at the 20 charters with the largest waitlists, the researchers found that most charters had the same size cohorts between kindergarten and 1st grades, and 6th and 7th grades. The Washington Post reported in 2015 that many charter operators in the city subscribed to this approach, considering it less “disruptive” than midyear entries.
Better policies?
The District of Columbia could solve this disparity in part by revisiting how it funds its schools. The city allocates funding based on October per-pupil counts, which means that when kids leave, they get to keep that share of the cash. Many states conduct multiple counts over the school year or rely on an average daily membership to assign funding. Both of those give schools more of an incentive to backfill seats.
Additionally, the states of Connecticut, Georgia, Idaho, and Massachusetts also require charters to backfill some vacancies, they note.
Any such change would probably require legislation through the city council, which funds schools, and possibly its office of the state superintendent, which handles accountability reporting and other functions. It is not clear whether the city’s charter school board could decide to require the charters it oversees to backfill on its own. The board did not immediately respond to requests for comment.
Campbell and Quirk noted that there are some limited instances when not backfilling could be appropriate. If a school is running a dual-language-immersion program that depends on a cohort of students advancing in their language abilities together, then it could makes some sense not to enroll a student who doesn’t have the necessary prerequisite skills, they said. But such exceptions should be few and far between.