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Student Attrition And "Backfilling" At Success Academy Charter Schools: What Student Enrollment Patterns Tell Us

This is the second of two posts on Success Academy Charter Schools. The first post was entitled “Student Discipline, Race and Eva Moskowitz’s Success Academy Charter Schools.”

Last fall, at a press conference called to respond to a New York Times exposé of efforts to “push out” targeted students from New York City’s Success Academy Charter Schools, Eva Moskowitz , the charter chain’s founder and CEO, described those practices as “an anomaly.”

“Our goal in suspending children or issuing any consequences,” Moskowitz told reporters, “is not to get rid of children or to have them leave our school. It is to have them have high standards of conduct.”

Last week, at a press conference called to respond to the New York Times publication of a video of a Success Academy model teacher berating a child for making a mistake in arithmetic, Moskowitz reiterated her claim that such practices were “anomalies.”

The notion that students were being “pushed out” in order to boost Success Academy scores on standardized exams was “just crazy talk,” Moskowitz told journalist John Merrow in a PBS interview.

Does the available evidence support Moskowitz’s claims? In search of an answer, 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 following charts capture those data. The first chart pools the student enrollment numbers across all Success Academy Charter Schools; the subsequent charts (below) are for the individual Success Academy Charter Schools that have four years or more of data.I have color coded the charts to make it easier for readers to follow the student cohorts as they pass through different grades.

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.

Success Academy Charter Schools has made a conscious decision to not fill seats opened up by student attrition in the upper grades of its schools. And 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.2

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

In New York City (NYC), the policy of refusing to fill seats vacated by student attrition is known by the unfortunate construction metaphor of failing to “backfill.” On a number of occasions, Moskowitz has forcefully defended Success Academy’s refusal to “backfill” the upper grades in which students take the state’s standardized exams. The full effect of this policy to not “backfill” can be seen in the only Success Academy cohort in the data that completed all eight primary school grades: the graduating class of Harlem Success Academy I had 32 students, less than half of the 73 students who started in the cohort eight years prior.

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.3 The poorest students are thus significantly overrepresented among school “leavers,” as are students who score poorly on high-stakes standardized exams.4 Indeed, the two phenomena are related.5

In response to criticism that the Success Academy Charter Schools “cream” their student populations to boost standardized test scores, Eva Moskowitz has argued that the attrition rates in her schools are lower than the average attrition rate for both NYC district schools and other charter schools. But the attrition rate is not the fundamental issue here; rather, it is the policy choice to not fill the empty seats left by student attrition.6

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.

Moskowitz also insists that her schools should not have to accept students from district schools who have received what she considers to be an inadequate education. Even if one accepted her questionable characterization of education in district schools, it is worth noting that she is insisting on a “one way” street: district schools should have to enroll the students who leave Success Academy Charter Schools, but Success Academy schools should not have to enroll students who leave district schools.

Even within the NYC charter school community, Success Academy’s policy of not “backfilling” open student seats in the exam-taking upper grades has its critics.  For the most part, other charter school leaders avoid any public censure of Moskowitz (although there was a notable lack of Success Academy defenders from the city’s charter school ranks last week and during last fall’s media firestorm). But Democracy Builders, a charter advocacy organization established by Democracy Prep Charter School founder Seth Andrew, minces no words in criticizing the failure of Success Academy Charter Schools and other “no excuses” charter networks to “backfill” empty student seats. “Some schools boast tantalizing proficiency percentages (on standardized tests – LC) and make easy exemplars,” Democracy Builders notes in its report No Seat Left Behind. “However, there is a wide variation of performance across the charter sector that is distorted by mobility and masked by the lack of backfill. Schools who lose students and gain percentage points give parents the false impression that a schools’ absolute number of proficient students is increasing each year. It isn’t.” Democracy Builders estimated that, during the 2013-14 school year, there were 2,500 empty student seats in NYC charter schools left unfilled by the refusal of Success Academy and like-minded charter networks to “backfill.”

Recent developments may well put Moskowitz’s defense of Success Academy’s discipline and enrollment policies to the test. The authorizer of the Success Academy charter schools, the SUNY Charter School Institute, has announced that it is launching an investigation into the disciplinary practices at Success Academy. And the U.S. Education Department’s Office of Civil Rights, responding to a complaint by the New York City Public Advocate, the Legal Aid Society, and a group of former and current Success Academy parents, will investigate claims that Success Academy schools illegally discriminate against students with special needs. The reaction to last week’s video publication by the New York Times can only increase the scrutiny of Success Academy Charter Schools.

Eva Moskowitz, New York City Charter School Center, and national charter school organizations such as the National Alliance for Public Charter Schools are now caught on the horns of an ethical and political dilemma. Under their tutelage, the charter school brand has been promoted around the claim that charter schools significantly outperform district public schools, with students’ standardized test scores as the “proof point” for this argument. When national studies made it clear that charter schools, as a whole, do not outperform district schools on tests scores, the focus of comparison was shifted to “high performing” charter school networks such as Success Academy. The most prominent elements in this polarized charter advocacy discourse – the continuous drumbeat of attacks on district schools as educational failures, with the call for mass closures of these schools; the demands for the continuous expansion of the charter sector at the expense of district public schools; the denigration of public school teachers and their unions; the fiercely adversarial and confrontational rhetoric – all ultimately rely upon this single foundational claim: that charter schools academically outperform comparable district schools, as demonstrated by student test scores. If this claim is lost, if the center of the discourse cannot hold, the entire discursive edifice comes apart.

But now the very policies that have allowed “no excuses” charter schools such as Success Academy to manipulate the contours of their student populations to produce high scores on standardized exams are under unprecedented investigation. 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. Do not look for Eva Moskowitz, the New York City Charter School Center and the National Association of Public Charter Schools to willingly travel down that road. A major political battle is in the making.


1 Readers should exercise caution in interpreting the data for Kindergarten and Grade One on the pooled chart. When Success Academy opens new schools, they start with both grades. As a consequence, there are substantial increases in the cohorts as they transition from Kindergarten to Grade One, as they include students from new schools that did not exist in the prior year. In subsequent grades, the cohorts reflect the same group of schools captured for Grade One.

2 The following list include all Success Academy charter schools in operation in spring 2015, when the most recent New York State report card was published and parents were looking for schools to enroll their children for September 2015. After each school, one finds the school year that the school started, the grades listed on the Success Academy website in spring 2015 and the grades listed on the Charter Center website. The contrast can be seen in the first school, Harlem Success I, where the Success website listed only grades K-4, even though it would be operating grades K-9 in September 2015, as the Center website indicates.


3 According to a recent New York City Independent Budget Office study, over 80,000 of New York City’s 1.1 million students are homeless – 7.5% of all students. The report does not break out the numbers of homeless students in the district schools and in the charter schools.

4 The latter point has been confirmed in research done by Marcus Winters for the conservative Manhattan Institute to counter arguments that charter school students cream their students. Transience multiplies the other negative effects of poverty on academic achievement, as it disrupts the educational process itself.

5 In the district schools, students who, during the middle of the school year, move into New York City or are forced to move from one city school to another are known as “over the counter” students, as they do not go through the normal admissions process. “Over the counter” students are disproportionately found in high needs categories – the poor, the homeless, new immigrants, English Language Learners, students with special needs, and students returning from incarceration. If a district school does not enroll “over the counter” students, it gets a bye on educating many of the city’s neediest students. The same is true of charter schools that do not “backfill.”

6 Indeed, a lower attrition rate could well be – at least in part – a reflection of a lower rate of poverty and transience in the student population. We do know that Success Academy Charter Schools have a lower rate of student poverty than the average for all NYC district schools, as measured by the economic disadvantage index on the New York State Education Department report cards – despite the fact that most of the Success schools have been located in the city’s poorest communities in Harlem, the South Bronx and central Brooklyn.

Issues Areas


Thank you for doing this research. However, one year's attrition data isn't as illuminating as a longitudinal study of what happens to the students who win the lottery for Kindergarten over the years in Success Academy schools. Just looking at a single year's attrition rate doesn't tell you much -- by the time the students get to 3rd grade many of the at-risk kids may have been replaced by children who are already working at grade level. Remember that the parent at the recent Success Academy press conference described how his child won a lottery spot for 2nd or 3rd grade and was told -- after being tested -- that she could only come to Success Academy if she repeated a year. (That child turned out to be gifted!) But imagine how easy it is to dissuade a parent of a "not up to snuff" child from coming by telling them their child couldn't join the grade he won the lottery for but could only enter the school if the parent agreed to repeat a year (or even two if they really don't want the kid!) as a condition of attending their school. A NY 1 news piece told the story of one girl whose family had happily celebrated their lottery win for a 1st grade spot until being told their child hadn't tested high enough and would not be allowed to accept that lottery spot without being forced to repeat Kindergarten again. The child didn't enroll. That is why the July 2015 report from the NYC Independent Budget Office is so important. The IBO did a longitudinal study of how many of the randomly selected Kindergarten students in NYC charter schools made it to 3rd, 4th, and 5th grade. Did they stay or did they leave? There were 53 charter schools in that study -- 4 of them were Success Academy schools -- and IN AGGREGATE those 53 schools lost 49.5% of their entering Kindergarten students by 5th grade. The NYC IBO did not reveal the individual attrition data on each of those 53 schools - which would illuminate how many children leave Success Academy - but they have the data for a researcher to request. It's shocking the report hid those Success Academy attrition rates from the public by ONLY using aggregated data because in that very same report the NYC IBO went to great trouble to disaggregate the test performance data of those charter schools so that Success Academy's test scores could be seen separately from all the other charter schools and not lumped into a big aggregated number which wasn't very good! In other words, the NYC IBO accommodated Success Academy by disaggregating the test performance scores of a large group of charter schools individually so the public could all see the huge discrepancy between Success Academy's high test performance rates and other charter schools. Is there ALSO a huge discrepancy between Success Academy's attrition rates of their starting Kindergarten class when compared to the other charter schools? For some reason when it came to attrition rates, the IBO chose to keep all that data lumped together which effectively hides whether Success Academy's attrition is higher than the other charter schools in that study. Why would the IBO disaggregate and rank Success Academy's test scores compared to those other charter schools and NOT disaggregate and rank their attrition rates compared to the other charter schools? Politics? If you get that data, it would also be revealing to see how many of those Success Academy students were held back and needed one or even two extra years before they were allowed to enter the testing grades (and how many of those kids asked to repeat a grade for the 2nd or 3rd time eventually left). The IBO study that said only 49.5% of the Kindergarten students in those 53 charter schools remained in the school when their cohort SHOULD have reached 5th grade, but if a child was only in 3rd grade when he had been in the school 5 or 6 years, that child was considered to be still in the school. One of Success Academy's least talked about "special sauces" is to simply keep holding students back as much as necessary. Remember some of those special needs kids whose parents sued the school were already 2 or 3 years behind their starting cohort! If Success Academy finds that 20% or 30% of their at-risk students need to repeat a year with their supposedly excellent teaching methods, wouldn't an honest charter school want to make that point? Finally, you mentioned backfill and it is clear that Success Academy actively uses backfill after Kindergarten to increase its class size. But it is HOW they backfill that needs to be looked at closely. As I mentioned above, there seems to be some unmonitored testing of certain students who win the lottery spots for older grades -- does it start as early as 1st grade -- that will certainly dissuade some low-performing students from enrolling. If every single open spot in 2nd or 3rd grade is ONLY filled with a student tested and deemed "allowed" (by whatever standard Success Academy wants) to join the grade he won a lottery spot for, you can guarantee that your school has a high number of students working at grade level! What percentage of the Success Academy students who make it to the testing years were not part of that original Kindergarten cohort but replacement students who had to prove they were working on grade level already before being allowed to join their class? Once we have the data from that IBO report as to how many of the starting Kindergarten students in 2008-2009 were part of that 4th and 5th grade testing cohort that got such high scores, and how many of those high scoring students were backfilled students who came in later and were tested before being allowed to join their appropriate class, much will be illuminated. Does any other charter school test the kids who win post-Kindergarten lottery spots BEFORE the child has even spent a few months in the classroom for their age-appropriate grade? Or is that something that only Success Academy does, and perhaps only for certain students? Here is a link to the report. The attrition data is on page 9 of the report. I hope you or another researcher will request the disaggregated attrition data of those 53 schools. Thank you again for your research and the graphs and tables above. It is clear that students leave and it is clear that new students come in to replace them after Kindergarten. The question is how many of the students who remain are the randomly selected Kindergarten winners of the lottery, and how many of the students are the backfilled (and tested?) students allowed to join their grade? With the disaggregated data from the IBO, much can be learned.

Let's be honest and think outside the box. Charter schools are failing lots of students. Absorb this as well. THE SACRED OATH FROM HEBRON (1929) TO TODAY | GED Programs | MICHELLE MALKIN TAKES ON A FEW SCHOOLS IN THE USA » August 04, 2014 EDUCATIONAL CONFERENCE CENTRAL ISLIP PUBLIC LIBRARY By Profesor Martin Danenberg “El Quijote del GED” with Queen Makkada, Jose M. Rios, and Angel Martinez. A quick word about Eva Moskowitz and Queen Makkada. Both Eva Moskowitz and Queen Makkada say that their schools must partner with parents. Queen Makkada does not have a lottery system for students because the students are in their neighborhood schools. Queen Makkada does not get paid a salary and Eva Moskowitz gets well over $300,000 a year. Queen works with about 300 parents that she has trained and about 85 percent of the children of these parents pass their state exams. Eva Moskowitz says that 82 percent passed math and 58 percent passed ELA exams. Eva Moskowitz says we cannot fix poverty if we do not fix education, but all over our nation urban areas are fighting poverty by fighting for a higher minimum wage and better salaries overall. Any differences in percentages may be due to better teaching to the test. Teaching to the test has to improve in school districts all over our nation. No Child Left Behind demanded 100 percent proficiency and anything less was considered a failing school. Diane Ravitch writes about this in The Reign of Error: The Hoax of the Privatization Movement and the Danger to America’s Public Schools. She tells us that America’s schools are not failing and you can see indications of that in this article. Essentially what Queen Makkada and Eva Moskowitz have done is similar. Queen did not take over a school that was closed down. The 300 parents come from various schools. The students at the Success Academies, too, come from various schools. Neither Queen Makkada nor Eva Moskowitz (I believe) has turned around a failing school. If the parents decide that their children should leave those ten schools and enter Success Academies in September, Queen Makkada would have to start all over and the Success Academies would reap the benefits. If Queen Makkada could accomplish all of this in Far Rockaway, can we not provide the same help to parents all over the city of New York, all over our nation, and all around the world? I believe we can and I am ready to proceed. I have no objection to charter schools, but charter schools really are not the answer to a huge problem and I do not consider Eva Moskowitz or Campbell Brown the Michael Jordans of education. For profit schools seem to be the answer, but I have just explained what is really needed and we can start in September to make a huge difference, even where there are no Success Academies. Move over Campbell Brown. Campbell Brown in on the board of Success Academies. The facts that Eva Moskowitz wrote about in her article in the New York Post are okay, but I ask that there be much more integrity in this great debate that is taking place. I know that I can provide that integrity. It is up to others to reach higher and give us the whole truth and that truth is that parents everywhere can make a great difference and teachers need to learn how to teach to the test. I know that teaching to a math test is easier than teaching to a reading test. Check the Success Academies results again. I am sure that teachers are also providing a well-rounded education in Queen Makkada’s home school and in the Success Academies, but even Queen Makkada entered a school during the last year school year and found superior things going on that seemed to surpass what Queen’s home school was doing. That school was in her district and she was really impressed. I know that White flight from the public schools has been replaced by Black flight and school safety is an important issue that triggers much of this flight. School safety is so much better today than it was in previous decades going back to the late 1960’s. Also the population change in the city, created by enormous gentrification, has reduced crime significantly. The newspapers normally credit good policing, but I just drove through areas of New York City undergoing great change (expensive housing) and even the Bronx Borough president is talking about that, too. Ruben Diaz, Jr. pointed out that there have been no murders in the old Fort Apache Precinct and he said the Bronx still has a bad reputation and he objects to it. I know that the Bronx borough president and its schools need the help of Queen Makkada. I know that it was so hard to educate people decades ago with crack epidemics and AIDS spreading across our nation. Eva Moskowitz talks like Wonderwoman or Superman without taking on the greatest challenges that the public schools have confronted all these years. Educating people in the last 10 years has only gotten easier. In my late father’s days, the graduation rate was only about 15 percent. Let us begin with Queen Makkada as she describes her participation in my educational conference. On July 24th, at 7 pm I had the pleasure to participate in an educational panel discussion in the Central Islip Public Library. The event was organized by El Profesor "GED", Martin Danenberg. It was great to hear the views and data that other panelists brought to the table, along with participants from the audience. As the Title 1 representative representing all of NYC DOE's Title 1 Parents and Children on Chancellor Fariña's, Chancellor Leadership Advisory Council, CLAC, it was a perfect opportunity to share how trained, organized and committed Parent Leaders and parents in District 27's district wide Title 1 Parent Advisory Council changed schools in District 27, especially the Rockaways.

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