School Choice

Lessons And Directions From The CREDO Urban Charter School Study

Last week, CREDO, a Stanford University research organization that focuses mostly on charter schools, released an analysis of the test-based effectiveness of charter schools in “urban areas” – that is, charters located in cities located within in 42 urban areas throughout 22 states. The math and reading testing data used in the analysis are from the 2006-07 to 2010-11 school years.

In short, the researchers find that, across all areas included, charters’ estimated impacts on test scores, vis-à-vis the regular public schools to which they are compared, are positive and statistically discernible. The magnitude of the overall estimated effect is somewhat modest in reading, and larger in math. In both cases, as always, results vary substantially by location, with very large and positive impacts in some places and negative impacts in others.

These “horse race” charter school studies are certainly worthwhile, and their findings have useful policy implications. In another sense, however, the public’s relentless focus on the “bottom line” of these analyses is tantamount to asking continually a question ("do charter schools boost test scores?") to which we already know the answer (some do, some do not). This approach is somewhat inconsistent with the whole idea of charter schools, and with harvesting what is their largest potential contribution to U.S. public education. But there are also a few more specific issues and findings in this report that merit a little bit of further discussion, and we’ll start with those.

Revisiting The Issue Of Charter Schools And Special Education Students

One of the most common claims against charter schools is that they “push out” special education students. The basic idea is that charter operators, who are obsessed with being able to show strong test results and thus bolster their reputations and enrollment, subtlety or not-so-subtlety “counsel out” students with special education plans (or somehow discourage their enrollment).

This is, of course, a serious issue, one that is addressed directly in a recent report from the Center for Reinventing Public Education (CRPE), which presents an analysis of data from a sample of New York City charter elementary schools (and compares them to regular public schools in the city). It is important to note that many of the primary results of this study, including those focused on the "pushing out" issue, cannot be used to draw any conclusions about charters across the nation. There were only 25 NYC charters included in that (lottery) analysis, all of them elementary schools, and these were not necessarily representative of the charter sector in the city, to say nothing of charters nationwide.

That said, the report, written by Marcus Winters, finds, among other things, that charters enroll a smaller proportion of special education students than regular public schools (as is the case elsewhere), and that this is primarily because these students are less likely to apply for entrance to charters (in this case, in kindergarten) than their regular education peers. He also presents results suggesting that this gap actually grows in later grades, mostly because of charters being less likely to classify students as having special needs, and more likely to reclassify them as not having special needs once they have been put on a special education plan (whether or not these classifications and declassifications are appropriate is of course not examined in this report).

Charter School Authorization And Growth

If you ask a charter school supporter why charter schools tend to exhibit inconsistency in their measured test-based impact, there’s a good chance they’ll talk about authorizing. That is, they will tell you that the quality of authorization laws and practices -- the guidelines by which charters are granted, renewed and revoked -- drives much and perhaps even most of the variation in the performance of charters relative to comparable district schools, and that strengthening these laws is the key to improving performance.

Accordingly, a recently-announced campaign by the National Association of Charter School Authorizers aims to step up the rate at which charter authorizers close “low-performing schools” and are more selective in allowing new schools to open. In addition, a recent CREDO study found (among other things) that charter middle and high schools’ performance during their first few years is more predictive of future performance than many people may have thought, thus lending support to the idea of opening and closing schools as an improvement strategy.

Below are a few quick points about the authorization issue, which lead up to a question about the relationship between selectivity and charter sector growth.

School Choice And Segregation In Charter And Regular Public Schools

A recent article in Reuters, one that received a great deal of attention, sheds light on practices that some charter schools are using essentially to screen students who apply for admission. These policies include requiring long and difficult applications, family interviews, parental contracts, and even demonstrations of past academic performance.

It remains unclear how common these practices might be in the grand scheme of things, but regardless of how frequently they occur, most of these tactics are terrible, perhaps even illegal, and should be stopped. At the same time, there are two side points to keep in mind when you hear about charges such as these, as well as the accusations (and denials) of charter exclusion and segregation that tend to follow.

The first is that some degree of (self-)sorting and segregation of students by abilities, interests and other characteristics is part of the deal in a choice-based system. The second point is that screening and segregation are most certainly not unique to charter/private schools, and one primary reason is that there is, in a sense, already a lot of choice among regular public schools.

Are Charter Caps Keeping Great Schools From Opening?

** Reprinted here in the Washington Post

Charter school “caps” are state-imposed limits on the size or growth of charter sectors. Currently, around 25 states set caps on schools or enrollment, with wide variation in terms of specifics: Some states simply set a cap on the number of schools (or charters in force); others limit annual growth; and still others specify caps on both growth and size (there are also a few places that cap proportional spending, coverage by individual operators and other dimensions).

A great many charter school supporters strongly support the lifting of these restrictions, arguing that they prevent the opening of high-quality schools. This is, of course, an oversimplification at best, as lifting caps could just as easily lead to the proliferation of the many unsuccessful charters. If the charter school experiment has taught us anything, it’s that these schools are anything but sure bets, and that even includes the tiny handful of highly successful models such as KIPP.*

Overall, the only direct impact of charter caps is to limit the potential size or growth of a state’s charter school sector. Assessing their implications for quality, on the other hand, is complicated, and there is every reason to believe that the impact of caps, and thus the basis of arguments for lifting them, varies by context – including the size and quality of states’ current sectors, as well as the criteria by which low-performing charters are closed and new ones are authorized. 

How Can We Tell If Vouchers "Work"?

Brookings recently released an evaluation of New York City’s voucher program, called the School Choice Scholarship Foundation Program (SCSF), which was implemented in the late 1990s. Voucher offers were randomized, and the authors looked at the impact of being offered/accepting them on a very important medium-term outcome – college enrollment (they were also able to follow an unusually high proportion of the original voucher recipients to check this outcome).

The short version of the story is that, overall, the vouchers didn’t have any statistically discernible impact on college enrollment. But, as is often the case, there was some underlying variation in the results, including positive estimated impacts among African-American students, which certainly merit discussion.*

Unfortunately, such nuance was not always evident in the coverage of and reaction to the report, with some voucher supporters (strangely, given the results) exclaiming that the program was an unqualified success, and some opponents questioning the affiliations of the researchers. For my part, I’d like to make a quick, not-particularly-original point about voucher studies in general: Even the best of them don’t necessarily tell us much about whether “vouchers work."