I’ve discussed before how many charter schools have a policy of not “backfilling” students who drop out. That is, students leave, but new students are not recruited. If the students who leave are score poorly on tests, this attrition will make charter schools appear to be better at increasing test scores than they really are.

One school charter school system that has a clear policy of doing this is the Success Academies of New York City. Leo Casey highlights what they do (boldface mine; footnotes at original post):

…I examined the student enrollment patterns at Success Academy Charter Schools, using the data currently available in the New York State Education Department’s school report cards….

The general pattern is unmistakable. In the early grades, student enrollment in Success Academy Charter Schools increases: Whatever losses the schools may suffer through student attrition are more than compensated for by the enrollment of new students. After Grade 2, however, the enrollment numbers begin to decline and do so continuously through the later grades. There are only small variations in this essential pattern among the different Success Academy Charter Schools.

In New York State, high stakes standardized exams begin at the end of Grade 3.

What a coincidence? And here’s how they do it:

…this is a deliberate, network-wide practice, as evidenced by Success Academy’s own website. When one compares the grades in each Success Academy Charter School, as listed on its website, with the grades in each school, as listed on the website of the New York City Charter School Center, one finds that the Charter School Center lists all the grades currently being provided under the school’s charter, while Success Academy lists many fewer grades – only those in which it is willing to enroll students.

In effect, the Success Academy website has the equivalent of a “do not apply” sign posted for each unlisted grade.

You’ll never guess what happens next! Or maybe you will:

How does this policy of not filling the seats left empty by student attrition shape the student population of Success Academy Charter Schools? Since the New York State Education Department’s school report cards do not disaggregate demographic data by grade level, it is not possible to track changes in the composition of student cohorts precisely. But we do know that the policy of refusing to “backfill” open seats does not fall randomly across all Success Academy students. The differentiated impact is self-evident in the case of “pushed out” students the schools do not want, such as those described in New York Times exposé, but it is also present in the case of students who leave without a “push” from the school. Transience is a central feature of poverty, and the greater the intensity of the poverty in which a student lives, the greater the transience she will experience: Homelessness is the ultimate expression of this reality. The poorest students are thus significantly overrepresented among school “leavers,” as are students who score poorly on high-stakes standardized exams. Indeed, the two phenomena are related….

To the extent that leaving students are not replaced with similar students, the student population will have fewer students living in poverty, fewer high needs students, and fewer students who score more poorly on standardized exams. Other schools may well have higher rates of attrition, but if they “backfill” their empty seats, the profile of their student population remains essentially the same.

As you might imagine, were these policies to be changed, this would have a huge (yooge!) effect on how we view public schooling:

There is increasing attention on the discriminatory effects of punitive discipline and excessive suspensions on “pushing out” students considered undesirable. It is hard to see how the U.S. Education Department can require district schools to move away from such policies and practices, while ignoring a high profile charter chain that employs them on an order of seven magnitudes greater. As the New York State legislature is confronted with demands to raise the cap on charter schools, it is hard to imagine that they could ignore the fact that the state’s charter schools could provide families with thousands of open seats right now, under the existing charter law, but choose not to do so.

To resolve these issues, Success Academy and similar charter school chains would have to make changes in policy and practice that would strike at their ability to engineer student populations to achieve high test scores. And this would put the charter school brand itself at risk.

Though it might actually start a meaningful discussion on how to improve educational outcomes for all students. One can hope anyway…