Critics frequently accuse charter schools of failing to adequately serve students with disabilities. In yet another high-profile example, The New York Times recently published an op-ed, under the snappish title "Charter School Refugees," which argued that the seeming success of charter schools in Harlem derives largely from their unwillingness to serve students with disabilities. Charter schools, the story goes, regularly push out students with special needs and force them back into traditional public schools. There are an untold number of anecdotes from parents who claim that their child was inappropriately "counseled out" of a charter school because of his disability.
To be sure, charter schools enroll, on average, a smaller proportion of students with disabilities than do surrounding traditional public schools. A 2012 report produced by the Government Accountability Office found significant gaps in almost every U.S. state.
But it's not enough to quantify this "special education gap." If we are to make sound policy, we need to understand where the gap comes from. Are charter schools really systematically excluding students with special needs? Or is there something else going on here?
I've now used student-level enrollment data to map the underlying causes of the special education gap in two large urban school systems: New York City and Denver. In each case the data allows me to track all students who enter charter and traditional public schools for a period of several years. The data also identifies when a student is classified as having a disability. These data allow me to exactly map the underlying causes of the differences in the percentage of students enrolled in special education in charter and traditional public schools.
The real stories in these cities, half a nation apart and facing very different circumstances, are not identical. But they are remarkably similar. Thus, these results likely speak to the conversation about charter schools nationwide.
It turns out the special education gap is not driven by students with disabilities exiting charter schools. In both cities, students with special needs are far less likely to leave their kindergarten school if it is a charter than if it is a traditional public school. In fact, after kindergarten, more students with disabilities enter a charter elementary school than leave it.
That is, the movement of students with disabilities across sectors actually tends to decrease the special education gap.
I do not mean to imply that no student has been inappropriately removed from a charter school. But the claim that such "counseling out" is driving the special education gap is simply inconsistent with student enrollment data. Students with special needs are highly mobile across schools. But they are more so when they attend traditional public schools than when they attend a charter.
If charters aren't systematically removing students with disabilities, what, then, explains the special education gap?
In New York City, the biggest driver of the special education gap is that students with disabilities -- particularly those with a speech or language impairment -- are less likely to apply to attend a charter school in kindergarten. Perhaps these students have been discouraged from applying. Or, perhaps they simply prefer the services offered in traditional public schools. (This isn't the case in Denver, where the special education gap is minor in kindergarten.)
Interestingly, a considerable portion of the special education gap derives not from student mobility, but from differences in how charter and traditional public schools classify their students. In both cities, charter elementary students are much less likely to be newly classified as having a disability than are students in the cities’ traditional public schools. In New York City, this difference is compounded by the fact that charter schools are much more likely to declassify students with existing disability classifications than are traditional public schools.
Notably, these classification differences across sectors are largest for the category of “specific learning disability,” which is the mildest and most subjectively diagnosed disability classification, and is thought by many to be over-classified within traditional public schools.
Anecdotal reports that charter schools systematically push out students with special needs are producing real policy responses. For instance, lawmakers in New York revised the state’s charter schools act to require charter authorizers to set enrollment and attendance targets for students with disabilities and consider the effort to meet these targets during renewal proceedings.
The facts from enrollment data suggest that a focus on eliminating "counseling out" will be unproductive. Since classification is the other main driver for the gap, fixed targets for special education rates within charter schools would encourage, and perhaps even force charter schools to push students into special education who might not require it.
Instead, policymakers should think about ways to increase charter applications among students with special needs. Further, they should look into why it is that traditional public schools are far more likely to classify their existing students as having a disability than are charters.
Any other policy response ignores the real facts in favor of anecdotes and unsubstantiated conventional wisdom.