I will protect your pensions. Nothing about your pension is going to change when I am governor. - Chris Christie, "An Open Letter to the Teachers of NJ" October, 2009

Sunday, May 28, 2017

Facts About Newark Charter Schools

It's just so old:
Their main criticisms of charters are that they skim the best students from the district and draw money away from district schools. But Newark's universal enrollment system puts a firm hand on the scale to ensure that charters take their fair share of harder-to-educate kids. And in Camden, charter leaders run neighborhood schools that guarantee enrollment to all area students. A kid's fate is not left to a lottery. [emphasis mine]
That is the Star-Ledger Editorial Board, once again writing a love letter to charters. Once again, I am here to set them straight.

I just went over the clear differences between charter school and public, district school student populations in Camden. A few tweaks of the code, and here's pretty much the same data for Newark.

As a proportion of total population, the Newark Public Schools enroll many more students with the costliest special education disabilities. We've been over this time and again: while some Newark charters have upped their enrollments of special education students, the students they do take tend to have the less-costly disabilities: Specific Learning Disabilities (SLD) and Speech/Language Disabilities (SPL).

The charters take very few students who are emotionally disturbed, or hearing impaired, or have intellectual disabilities, or any of the other higher-cost disabilities. And when you look at the counts of students as opposed to the proportions, you can see just how stark the differences between the two sectors really are.

There's also the disparity in Limited English Proficient (LEP) students, who also cost more to educate:

It is unconscionable that Newark's charters are being "held harmless" in their funding while the district bears this enormous fiscal burden.

Just to be clear: I don't think charters should be attempting to educate these students with special needs. By all indications, they don't have the capacity to do the job correctly.

NPS has a much lower "student load" per support staff member than the charters. These support staff include counselors, occupational and physical therapists, nurses, psychologists, social workers, learning disability teacher consultants, reading specialists, sign language interpreters, speech correction specialists, and so on. It would be highly inefficient to staff every charter school and network in the city with all of these staff.

But that's precisely the problem with charter proliferation: it creates redundant school governance that taxes the entire system. And that's not the only issue:

As I've documented many times, charter school teaching staffs have far less experience than public school staffs. Not only does this create a fiscal burden on charters, who must continually retrain their churning teaching staffs; it creates a "free rider" problem for hosting public schools.

In the aggregate, teacher salaries in the first decade for district and charter teachers in Newark are fairly close. Some of the large charter networks, like TEAM/KIPP and Uncommon/North Star, pay better than the district; most of the mom-and-pop charters pay worse. But that's only until about year ten; after, NPS teachers enjoy a significant bump in pay.

But the charters don't have to worry about competing with NPS on salary at that point: because their staffs churn so much, few of their teachers have more than a decade's worth of experience. What economist Martin Carnoy has suggested is that the charters are getting a "free ride":
The “free rider” aspect of teacher costs in private schools, whether voucher or charter, means that the supply of young people entering the teaching profession is maintained by the salary structure and tenure system in public education. Without this structure, many fewer individuals would take the training needed to become certified to enter teaching. Since teaching salaries are low compared with other professions, the prospect of tenure and a decent pension provides the option of security as compensation for low pay. This pool of young, trained teachers is available to voucher and charter schools, generally at even lower pay than in the public sector and without promise of tenure or a pension, but with the possibility of training and experience. Thus, the public education employment and salary system “subsidizes” lower teacher costs in private and charter schools. In other words, for private schools to have lower costs, it is necessary to maintain a largely public system that pays teachers reasonable (but still low) salaries and provides for a teacher promotion ladder and job security. [emphasis mine]
There is, however, a cost for maintaining an inexperienced staff:

Newark charters spend much more per pupil on administration than NPS schools. Part of this is due to charters being unable to leverage economies of scale like the district schools. Part of it is undoubtedly because the schools need more administrators to support more inexperienced teachers.

Fortunately for some of the big charter networks -- TEAM/KIPP, Uncommon/North Star, and Great Oaks in particular -- they are able to access resources from their regional and national networks. This includes large amounts of philanthropic funding, capital for building new facilities, and tutors whose costs are supported from federal funds.

The SLEB claims charters get "no capital funds." I don't know where they got this idea, but it's just wrong; charters may not draw from the same state pool as district schools, but plenty of other monies are available to them for facilities.

NPS gave a sweetheart deal to charter operators, who now get to use public monies to transfer public assets to private control. Back in 2014, Owen Davis reported that all of the qualified school construction bonds New Jersey received went to charters. Three charters got to locate in Teachers Village, built with all sorts of financial goodies offered by the state and the feds. And let's not forget that a whole bunch of the Zuckerberg money went to the charter sector.

Let's review:
  • Newark charters enroll far fewer students who have costly special education disabilities, or who are Limited English Proficient, than NPS schools.
  • Compared to NPS schools, Newark charters do not have the staffs in place to properly educate these high-needs students.
  • Newark charter staffs have much less experience than NPS staffs.
  • Newark charters are, consequently, "free riding" on NPS schools, which reward teachers for their experience.
  • Newark charters have much higher administrative costs than NPS schools.
  • Newark charters have access to all sorts of outside funding and capital that NPS cannot utilize.
I've not been one to call for closing Newark's charter schools; at this point, the upheaval might -- might -- be more detrimental to the students enrolled in those schools than the damage being done to the whole system. Some might not like my point of view on this, but I don't think it's right to chance making Newark's schooling system even more chaotic than it already is.

But there is a clear fiscal drain on the Newark Public Schools due to charter proliferation. And it's very hard to justify the harm this causes by pointing to some, frankly, underwhelming gains on standardized tests. 

But the SLEB doesn't see it that way:
The key threats now facing charters in New Jersey are a moratorium on all charter growth, and a local vote being required to open any new charter school. 
Because top charters in Newark and Camden expand year by year, a moratorium would force sixth graders to transfer back to the district schools, rather than being allowed to continue on to 7th grade. That would clearly hurt kids. And since the teacher's union dominates school board elections with low turnout, giving the board veto power is akin to strangling any new charter in its crib. The better gauge is clear parental preference.
First of all: Maybe turnout is low in school board elections because Newark has been under state control for over two decades, which means the election is largely meaningless.

Second: What "would clearly hurt kids" who are enrolled in NPS is the growth of a system that holds charter schools harmless in the face of state aid cuts, concentrates special needs children into the public schools, free-rides on teacher salaries, drives more funding into administration, doesn't allow for economies of scale, and puts public assets into private hands.

Don't the kids enrolled in NPS deserve well-resourced schools? Don't their parents deserve democratic control of their school system? Shouldn't they have the same say over their schools that suburban parents have over theirs?

A moratorium on charter growth in Newark -- and across the state -- is a reasonable policy. Don't agree? Fine, but the idea that charters are unquestionably beneficial to cities like Newark is shallow and ignorant.

The Star-Ledger, after its flight from Newark (h/t Wallace Strobe).

Saturday, May 27, 2017

The Facts About Charter School Finances in Camden, NJ

Here's Part I of my U-Ark series.

Here's Part II.

This post really should be called "U-Ark Screws Up A Charter School Revenue Study, AGAIN: Part III," as it is a follow-up to my last two posts about how the University of Arkansas Department of Education Reform messed up its latest study of charter school revenues. I'm retitling it, however, because I think the facts I present below have significance beyond critiquing U-Ark's report.

As I showed, U-Ark's claim that Camden's charter sector is receiving far less funding than the city's public schools is completely bogus (and this almost certainly applies to the other cities in their study). They double count revenues going to charter schools without attributing them to those schools' students. They don't understand that since the district has the responsibility for transporting charter students, revenues allotted for that purpose shouldn't be attributed to the district.

I'd go on about the many other methodological failures in the study, but Bruce Baker covered them when he reviewed U-Ark's report from 2014. Amazingly, U-Ark cites Baker in their latest report -- but then goes back and makes the same mistakes. Which wouldn't be so bad if the study was being ignored and wasn't influencing policy makers; unfortunately, it appears stakeholders are heeding the study's conclusions.

This, by the way, is a huge problem in education policy journalism right now: reporters will often trumpet a "new study" that knowledgable critics haven't had time to properly vet. Even if it's a piece of junk, it still gets attention; at best, the critics are given a "he said-she said" positioning that leads stakeholders to believe that even if the study has problems, it's probably still making at least a somewhat valid point.

Let's use Camden's charters and the U-Ark study as an example of why this is such a problem. Here's a quote from page 14:
Inequitable funding between public charter schools and TPS could be due to differences in the number of students identified as requiring SPED [special education] services, as described in Table 2. To test this ubiquitous claim regarding the charter school funding gap, we depart from our normal approach of focusing exclusively on revenues and consider SPED expenditures by both school sectors.

The Table 3 column labeled “SPED Expenditure Gap Per Student” presents the results from subtracting the amount of dollars spent per student in the charter sector from the amount of dollars spent per student in TPS sector. All totals are positive, indicating that TPS spend more on SPED than charters in all 14 of our metropolitan areas. The largest SPED expenditure gap is in Camden, where TPS spend $3,383 more per student on SPED than charters spend. The smallest SPED expenditure gap is in Tulsa, where TPS only spend $32 more per pupil on SPED than charters do. [emphasis mine]
As I've noted previously, the documentation of data sources in this report is so bad it's impossible for me to replicate the report's analyses. There's also a serious problem when making these comparisons, as the amount spent on special education is not necessarily the amount that should be spent. In other words, if the charters or TPSs are short-changing what ought to be spent to properly educate a special needs student, that's going to affect the spending "gap." In no way, then, is this analysis adequate for making claims about charters being underfunded.

There's one additional flaw here, and it's huge: Not all special education students are the same, which affects how much a school spends. So far as I can tell -- again, the documentation of methods is so lacking I can't say for sure -- U-Ark treated special education status as a binary variable: either a child is classified or she is not. But that is a terrible way of assessing the true reasons for a charter school revenue "gap":

2014 is the last year for which we have good data on the types of learning disabilities students have. Specific Learning Disabilities (SLDs) and Speech/Language disabilities (SPL) are lower-cost classifications (that comes directly from a report commissioned by the state in 2011). Students with the other disabilities, such as autism, traumatic brain injury, visual impairment, and so on, require more resources to receive an adequate education.

Very few students with the costliest learning disabilities enroll in Camden's charter schools; this is also true across New Jersey, and across the nation

Let's look at this as a percentage of total student population:

As a percentage, Camden City Public Schools enroll far more special needs students with the costliest disabilities. It's worth noting that most of these students in the charters are classified as "Other Health Impairment," a catch-all phrase that includes students with asthma and ADHD. Which means many of these students could still have disabilities that are relatively easily treated and don't require much support.

This alone is enough evidence to dismiss U-Ark's blanket claim that special education status isn't a major factor in Camden's revenue "disparity." But let me point out a few more pertinent facts U-Ark simply doesn't consider:

The percentage of Limited English Proficient (LEP) students in CCPS is consistently greater than the percentage in the charter schools. This obviously requires CCPS to spend more per pupil, as LEP students needs special services.

Camden has many free lunch-eligible (FL) students in both the charters and in CCPS schools. The New Jersey funding formula, SFRA, directs more resources to schools with more at-risk students (as it should). But recently, CCPS moved to a universal enrollment system for subsidized student meals. I certainly applaud this, but it makes research more difficult. There is now no incentive for CCPS families to enroll in the program; in contrast, charters do rely on FL enrollment numbers to pass more money through to them from the district. Which makes the FL statistics unreliable.

But the measure was never very good to begin with: all it shows is how many students fall below 130 percent of the poverty line. There are lots of reasons to believe there's great variation within that group of students. I'm not sure U-Ark could have done anything about this, but they should at least acknowledge the issue.

Some other points:

The charter sector relies on staffs that have far less experience than CCPS teachers. We know teachers gain the most in effectiveness in their first few years, so this is a serious concern. But there's another problem related to U-Ark's study.

CCPS has many more teachers with a decade or two of experience than the charters. This affects the payrolls of each sector.

I was a bit surprised when I saw this, because teacher salaries tend to be much lower in charter schools. But starting around year 3, salary schedules are about the same... until you get to the second decade. That's when CCPS salaries start to rise at a steeper slope, leaving charter salaries behind.

Why does this matter? As Martin Carnoy has recently pointed out, it sets up a "free rider" problem for CCPS. Charter teachers accept less pay because they don't expect to stay in the job very long. Maybe they will move on to another field; maybe they'll switch over to a public school district, which will give them better pay in the future. The charters can offer less pay now because teachers can expect more pay later when they aren't working in the charter.

Between the special needs students and the free-riding on salaries, it's increasingly clear the charter sector couldn't sustain its model without the public schools spending more money. But the charters still draw significant revenues. What do they spend it on?

Charter school administrative spending is far in excess of public school spending. It's possible charters have to spend more because they churn their teachers, requiring more administrators to work with perpetually inexperienced staffs. It's also likely charters are too small to achieve economies of scale, a fact Bruce Baker pointed out recently.

Charter schools spend far less on student support services, likely because they have fewer students who need those services. Services include child study teams, therapists, school nurses, and other staff who spend much of their time serving students with special education needs. Some charters don't report any spending on these services.

None of these realities are explored in U-Ark's report. And yet every one of them is relevant to U-Ark's claim that: "Public charter schools in Camden, New Jersey, are the most underfunded, receiving an average of $14,771 less in per-pupil funding that TPS, representing a 45 percent funding inequity."

This is a bogus, sloppy, unwarranted comparison; no policy should be enacted based on U-Ark's claims. In fact, based on their analysis of Camden alone, the entire report should simply be dismissed as unreliable.

Again: this isn't anything new. U-Ark has been repeatedly criticized for its work in this area. And yet they plow ahead, with the blessing of both their funders and the university that hosts them. Why?

You tell me.

Sunday, May 21, 2017

Random Thoughts On Using VAM for Teacher Evaluation

You may have read the piece in the New York Times today by Kevin Carey on the passing of William Sanders, the father of idea of using value-added modeling (VAM) to evaluate teachers. Let me first offer my condolences to his family.

I'm going to skip a point-by-point critique of Carey's piece and, instead, offer a few random thoughts about the many problems with using VAMs in the classroom:

1) VAM models are highly complex and well beyond the understanding of almost all stakeholders, including teachers. Here's a typical VAM model:

Anyone who states with absolute certainty that VAM is a valid and reliable method of teacher evaluation, yet cannot tell you exactly what is happening in this model, is full of it.

There was a bit of a debate last year about whether it matters that student growth percentiles (SGPs) -- which are not the same as VAMs, but are close cousins -- are mathematically and conceptually complex. SGP proponents make the argument that understanding teacher evaluation models are like understanding pi: while the calculation may be complex, the underlying concept is simple. It is, therefore, fine to use SGPs/VAMs to evaluate teachers, even if they don't understand how they got their scores.

This argument strikes me as far too facile. Pi is a constant: it represents something (the circumference of a circle divided by its diameter) that is concrete and easy to understand. It isn’t expressed as a conditional distribution; it just is. It isn’t subject to variation depending on the method used to calculate it; it is always the same. An SGP or a VAM is, in contrast, an estimate, subject to error and varying degrees of bias depending on how it is calculated.

The plain fact is that most teachers, principals, school leaders, parents, and policy makers do not have the technical expertise to properly evaluate a probabilistic model like a VAM. And it is unethical, in my opinion, to impose a system of evaluation without properly training stakeholders in its construction and use.

2) VAM models are based on error-prone test scores, which introduces problems of reliability and validity. Standardized tests are subject to what the measurement community often calls "construct-irrelevant variance" -- which is just a fancy way of saying test scores vary for reasons other than knowing stuff. Plus there's the random error found in all test results, due to all kinds of things like testing conditions. 

This variance and noise causes all sorts of issues when put into a VAM. We know, for example, that the non-random sorting of students into teacher classrooms can create bias in the model. There is also a very complex issue known as attenuation bias when trying to deal with the error in test scores. There are ways to ameliorate it -- but there are tradeoffs. 

My point here is simply that these are very complicated issues and, again, well beyond the apprehension of most stakeholders. Which dictates caution in the use of VAM -- a caution that has been sorely lacking in actual policy.

3) VAM models are only as good as the data they use -- and the data's not so great. VAM models have to assign students to teachers. As an actual practitioner, I can tell you that's not as easy as it sounds. Who should be assigned a VAM score for language arts when a child is Limited English Proficient (LEP): the ELL teacher, or the classroom teacher? What about special education students who spend part of the school day "pulled out" of the homeroom? Teachers who team teach? Teachers who co-teach?

All this assumes we have data systems good enough to track kids, especially as they move from school to school and district to district. And if the models include covariates for student characteristics, we need to have good measures of students' socio-economic status, LEP status, or special education classification. Most of these measures, however, are quite crude.*

If we're going to make high-stakes decisions based on VAMs, we'd better be sure we have good data to do so. There's plenty of reason to believe the data we have isn't up to the job.

4) VAM models are relative; all students may be learning, but some teachers must be classified as "bad." Carey notes that VAMs produce "normal distributions" -- essentially, bell curves, where someone must be at the top, and someone must be at the bottom.

I've labeled this with student test scores, but you'd get the same thing with teacher VAM scores. Carey's piece might be read to imply that it was a revelation to Sanders that the scores came out this way. But VAMs yield normal distributions by design -- which means someone must be "bad."

General Electric's former CEO Jack Welch famously championed ranking his employees -- which is basically what a VAM does -- and then firing the bottom x percent. GE eventually moved away from the idea. I'm hardly a student of American business practices, but it always struck me that Welch's idea was hampered by a logical flaw: someone has to be ranked last, but that doesn't always mean he's "bad" at his job, or that his company is less efficient than it would be if he was fired.

I am certainly the last person to say our schools can't improve, nor would I ever say that we have the best possible teaching corps we could have. And I certainly believe there are teachers who should be counseled to improve; if they don't they should be made to leave the profession. There are undoubtedly teachers who should be fired immediately.

But the use of VAM may be driving good candidates away from the profession, even as it is very likely misidentifying "bad" teachers. Again, the use of VAM to evaluate systemic changes in schooling is, in my view, valid. But the argument for using VAM to make high-stakes individual decisions is quite weak. Which leads me to...

5) VAM models may be helpful for evaluating policy in the aggregate, but they are extremely problematic when used in policies that force high-stakes decisions. When the use of test-based teacher evaluation first came to New Jersey, Bruce Baker pointed out that its finer scale, compared to teacher observation scores, would lead to making SGPs/VAMs some of the evaluation but all of the decision.

But then NJDOE leadership -- because, to be frank, they had no idea what they were doing -- made teacher observation scores with phony precision. That led to high-stakes decisions compelled by the state based on arbitrary cut points and arbitrary weighting of the test-based component. The whole system is now an invalidated dumpster fire.

I am extremely reluctant to endorse any use of VAMs in teacher evaluation, because I think the corrupting pressures will be bad for students; in particular (and as a music teacher), I worry about narrowing the curriculum even further, although there are many other reasons for concern. Nonetheless, I am willing to concede there is a good-faith argument to be made for training school leaders in how to use VAMs to inform, rather than compel, their personnel decisions.

But that's not what's going on in the real world. These measures are being used to force high-stakes decisions, even though the scores are very noisy and prone to bias. I think that's ultimately very bad for the profession, which means it will be very bad for students.

Carey mentions the American Statistical Association's statement on using VAMs for educational assessment. Here, for me, is the money quote:
Research on VAMs has been fairly consistent that aspects of educational effectiveness that are measurable and within teacher control represent a small part of the total variation in student test scores or growth; most estimates in the literature attribute between 1% and 14% of the total variability to teachers. This is not saying that teachers have little effect on students, but that variation among teachers accounts for a small part of the variation in scores. The majority of the variation in test scores is attributable to factors outside of the teacher’s control such as student and family background, poverty, curriculum, and unmeasured influences. 
The VAM scores themselves have large standard errors, even when calculated using several years of data. These large standard errors make rankings unstable, even under the best scenarios for modeling. Combining VAMs across multiple years decreases the standard error of VAM scores. Multiple years of data, however, do not help problems caused when a model systematically undervalues teachers who work in specific contexts or with specific types of students, since that systematic undervaluation would be present in every year of data. 
A VAM score may provide teachers and administrators with information on their students’ performance and identify areas where improvement is needed, but it does not provide information on how to improve the teaching. The models, however, may be used to evaluate effects of policies or teacher training programs by comparing the average VAM scores of teachers from different programs. In these uses, the VAM scores partially adjust for the differing backgrounds of the students, and averaging the results over different teachers improves the stability of the estimates [emphasis mine]
Wise words. 

NJ's teacher evaluation system, aka "Operation Hindenburg."

* In districts where there is universal free-lunch enrollment,parents have no incentive to fill out paperwork designating their children as FL-eligible. So even that crude measure of student economic disadvantage is useless.

Saturday, May 20, 2017

U-Ark Screws Up A Charter School Revenue Study, AGAIN: Part II

Here's Part I of this series.

Here's Part III, which is actually a presentation of relevant facts about Camden, NJ charter school finances.

If this is true, it's really disturbing:
Colorado’s General Assembly on Wednesday passed a bill giving charter schools the same access to a local tax funding stream as district schools have, The Denver Post reported.
The bipartisan compromise measure, which supporters say is the first of its kind in the nation, would address an estimated $34 million inequity in local tax increases. It came a day after the University of Arkansas released a study that found charter schools receive $5,721 less per pupil on average than their district counterparts — a 29 percent funding gap. [emphasis mine]
It is, of course, standard operating procedure for outfits like the U-Ark Department of Education Reform to claim their work led to particular changes in policy; that's how they justify themselves to their reformy funders.  Maybe the connection between the report and the Colorado legislation (which is really awful -- more in a bit) is overblown...

But if the U-Ark report did sway the debate, that's a big problem. Because the report is just flat out wrong. 

As I explained in Part I, the claim that Camden, NJ, has a huge revenue gap between charters and public district schools seems to be based on an utterly phony comparison: all of the revenue, both charter and district, is linked to only the CCPS students -- not the charter students. Because the data source documentation in the report is so bad, I can't exactly replicate U-Ark's figures, so I invited Patrick Wolf and his colleagues to contact me and explain exactly how they got the figures they did.

So far, they remain silent.

But that isn't surprising. When U-Ark put out its first report in 2014, Bruce Baker tore it to shreds in a brief published by the National Education Policy Center. The latest U-Ark report cites Baker's brief, so they must have read it -- but they never bothered to answer Baker's main claim, which is that their comparisons are wholly invalid.

Further, what I documented in the last post is only one of the huge, glaring flaws in the report. Let me point out another, using Camden, NJ again as an example. We'll start by looking U-Ark's justification for using the methods they do:
This is a study of the revenues actually received by public charter schools and TPS. Revenues equal funding. Revenues signal the amount of resources that are being mobilized in support of students in the two different types of public schools. Some critics of these types of analyses argue that our revenue study should, instead, focus on school expenditures and excuse TPS from certain expenditure categories, such as transportation, because TPS are mandated to provide it but many charter schools choose not to spend scarce educational resources on that item. [emphasis mine]
"Choose" not to spend the revenues? Sorry to be blunt, but that statement is either deliberately deceptive or completely clueless.* In New Jersey, hosting public school districts are required to provide transportation for charter school students. The charters don't "choose" not to spend on transporting the kids; they avoid the expense because the district picks up the cost.

Baker pointed this out explicitly in his 2014 brief -- but U-Ark, once again, refuses to acknowledge the problem, even though we know for a fact they read Baker's report, because they cite it repeatedly.

And it gets worse.

For the sake of illustration, here's a simplified conceptual map of what Camden's public district school bus system might look like. We've got neighborhood schools divided into zones, and buses transporting children to their neighborhood school.** There are exceptions, of course, primarily for magnet and special needs students, but the system on the whole is fairly simple.

Now let's add some "choice":

There has been a marked decline in "active transportation" -- walking or biking -- to school over the past few decades, and school "choice" is almost certainly a major contributor. As we de-couple schools from neighborhoods (which may well have many other pernicious effects), transportation networks become more complex and more expensive.

As I said: New Jersey law requires public school districts like Camden to pay for transportation of charter school students. Which means all of these extra costs are borne solely by the district.

And how much does this cost Camden's charter sector?

So any comparison of revenues that doesn't exclude transportation -- and, again, it appears that U-Ark didn't exclude it, although their documentation is so bad we can't be sure -- is without merit. Claiming that charter schools have a revenue gap when they use services paid for by public district schools makes no sense.

Folks, this issue is so simple that it doesn't require an advanced understanding of school finance or New Jersey law to understand it. Which makes it all the more incredible the U-Ark team didn't account for it in their findings. And again: if the Colorado Assembly made their decision to raise the funding for charters -- at the expense of public district schools -- on the basis of a report that is this flawed...

Let's take a look at some better -- not perfect, but better -- financial comparisons between Camden's charters and CCPS next.

 * Granted, it might be both...

** It's worth noting that in a dense city like Camden, many of the students will be within walking distance of their neighborhood school. But when you introduce "choice," you make the school system much less walkable, because students are likely traveling greater distances. I was at a conference at Rutgers yesterday where researchers were looking into this issue -- more to come...

Tuesday, May 16, 2017

U-Ark Screws Up A Charter School Revenue Study, AGAIN: Part I

Here's Part II of this series.

Here's Part III, which is actually a presentation of relevant facts about Camden, NJ charter school finances.

As someone who spends a good bit of his time debunking many of the claims of the education reformsters, one continuing frustration is how many of them don't seem to learn their lessons. Certainly, we can have good faith debates about education policy, and reasonable people can disagree on many things...

But when you've been called out in public for making a big mistake, and you don't at least attempt to correct yourself... well, it's hard to take you seriously -- even if other, less discriminating minds do.

We parents all have heard the claim that something wasn’t fair. “Suzie got a bigger piece of cake than I did!” “Tommy got to go fishing while I had to clean the garage!” “Malachi had a lot more money spent on his education because you sent him to a traditional public school and me to a public charter school!” Well, maybe we haven’t actually heard that last one very often but it would be a more legitimate gripe than the other ones. 
Students in public charter schools receive $5,721 or 29% less in average per-pupil revenue than students in traditional public schools (TPS) in 14 major metropolitan areas across the U. S in Fiscal Year 2014. That is the main conclusion of a study that my research team released yesterday.
This is from the crew at the University of Arkansas's "Department of Education Reform" -- yes, there is such a thing, I swear -- led by the author here, Patrick Wolf. The study Wolf's team produced purports to show that charters are getting screwed out of the revenues they deserve, which are instead flowing to public district schools.

(Side note: if charters "do more with less," why do they need the same money as public district schools? Isn't that part of their "awesomeness"?)

But here's the thing: the methods this study uses are similar to a study they produced back in 2014 -- a study that was thoroughly debunked a month later. In a brief published by the National Center for Education Policy, Dr. Bruce Baker* notes that even if we put aside many problems the U-Ark study has with documenting its data sources and explaining its methodologies, one enormous flaw renders the entire report useless:

As mentioned earlier, the major issue that critically undercuts all findings and conclusions of the study, and any subsequent “return on investment” comparisons, is the report’s misunderstanding of intergovernmental fiscal relationships. Again, as the authors note, they studied “all revenues” (not expenditures), because studying expenditures, while “fascinating” would be “extremely difficult” (Technical appendix, p. 385). 
Any “revenue per pupil” figure includes two parts that may significantly affect the figure. What goes into the total revenue measure? And how are pupils counted? If one’s goal is to compare “revenues per pupil” of one entity to another, one must be able to appropriately align the correct revenue measure with the correct pupil measure for each entity. That is, for the district, one must identify the revenues intended to provide services to the district’s pupils and revenues intended to provide services to the charter school’s pupils. If numbers are missed orworse yetwrongly attributed, the comparison becomes invalid and misleading. [emphasis mine]
Baker cites several examples of how U-Ark gets this basic idea wrong time and again -- including, in his first example, U-Ark's analysis of Newark, NJ:
One can get closer to the $28,000 figure by dividing total revenue for that year by the district enrollment, excluding sent pupils (charter school, out of district special education, etc.). But this would be particularly wrong and the result substantially inflated because the numerator would include all revenues for both district and sent charter students, but the denominator would include only district students
Again, Baker pointed this out in 2014. But guess what? By all appearances, U-Ark made the same mistake once again in 2017. Let me see if I can explain this with a few pictures.

Unlike the U-Ark report, I'm going to tell you exactly where I'm getting my data for all these slides. The school year is 2013-14, just like the U-Ark report. The fiscal data comes from the User-Friendly Budget Guide** published by the New Jersey Department of Education; U-Ark says in its data comes from the NJDOE, so the figures should be the same. I get my charter enrollment numbers from the Enrollment data of the NJDOE, using the 2013-14 files.

There were, according to these sources, 17,273 students in Camden's total enrollment for 2013-14. These include contracted pre-school and out-of-district placements, which we will set aside for now (even though that is a deeply flawed thing to do -- more later). If we take the total full-time enrollment -- 15,546 -- and subtract 4,251 charter students, we get 11,295 Camden City Public School students.

Total revenues for the district in that year were $369,770,349. This included $54,902,533 in transfers to the Camden charter schools. Understand that this was not necessarily the only source of revenue for the charters, who might also collect funds directly from the federal government or from private sources. It's also worth pointing out here that all 4,251 Camden charter students may not come from Camden (although it's safe to assume the vast majority are city residents). But, as we'll see, that doesn't matter anyway.

Using these figures, U-Ark steps in to make its per pupil calculations. In the numerator is the revenue  collected by the district or the charter schools; in the denominator are the students enrolled in each sector.

See the problem?

If we use all of the $370 million in the district's per pupil figure, but we only count the students in CCPS and not the charters, we wind up double-counting about $55 million. Because that money is in both the district per pupil figure and in the charter figure.

Even U-Ark admits they should not do this:

That $370 million figure -- a figure, by the way, that is deeply flawed (more in Part II), should not be the figure that U-Ark uses to calculate CCPS's per pupil figure. I'm not saying this: U-Ark is.

So did they?

My calculation using these figures comes out to $32,738 -- which is very close to U-Ark's figure of $32,569.

Like I said, there are several reasons the figures don't match exactly: precise charter enrollment figures, including various students in out-of-district placements, minor adjustments to the revenue, etc.

But it's clear that Wolf and his U-Ark team used the wrong revenue figure when making their calculation of Camden's per pupil spending; worse, they made the same mistake they made in 2014, even after they had been publicly corrected!

(Side note: we know they read Bruce Baker's review of their earlier report, because they cite it multiple times.)

Now, as I'll explain in the next post, fixing this problem still makes for a deeply flawed analysis. But let's suppose, just for illustration purposes, they had corrected it. What would the figure be?

Here, we subtract the charter school transfer (find it on page 5 of the User-Friendly Summary). Which, according to U-Ark themselves, is the correct way to approach the calculation. What's the result?

Again, this is a deeply flawed comparison. But it's a much smaller gap than using U-Ark's methods.

Let me end this part by addressing Professor Wolf and his team directly:

Gentlemen, I have shown in this post exactly where my data came from. Maybe you have different, equally credible sources. None of us would know, however, because your sole citation for state data is: "New Jersey Department of Education, School Finance." (p. 33) If you'd care to share your sources, your data, and how you arrived at your calculations (in appropriate detail to allow for replication, a common standard in our field), then please do; I'll happily publish them here. You can reach me at the email address on the left side of the blog.

But as it stands right now, there is more than enough evidence, in my opinion, to entirely dismiss your report and its conclusions.

Part II in a bit...

ADDING: Previous atrocities have been documented. 

* As always: Bruce is my advisor in the PhD program at Rutgers GSE.

** I use the 2015-16 guide because it gives the latest "actual" figures for 2013-14 available from NJDOE.

Thursday, May 11, 2017

Attrition in Denver Charter Schools

Earlier this month David Leonhardt of the New York Times wrote yet another column extolling the virtues of charter schools. I feel like a broken record when I say, once again, that education policy dilettantes like Leonhardt don't seem to understand that it requires more than a few studies showing a few charters in a few cities in a few select networks get marginally better outcomes on test scores to justify large-scale charter expansion.

There are serious cautions when it comes to the proliferation "successful" charters, starting with the fiscal impact on hosting districts as charters expand. We should also be concerned about the abrogation of student and family rights, the lack of transparency in charter school governance, the narrowing of the curriculum in test-focused charters, the racially disparate disciplinary practices in "no excuses" charters, and the incentives in the current system that encourage bad behaviors.

But let's set all that aside and look at the evidence Leonhardt presents to justify his push for more charters:
Unlike most voucher programs, many charter-school systems are subject to rigorous evaluation and oversight. Local officials decide which charters can open and expand. Officials don’t get every decision right, but they are able to evaluate schools based on student progress and surveys of teachers and families. 
As a result, many charters have flourished, especially in places where traditional schools have struggled. This evidence comes from top academic researchers, studying a variety of places, including Washington, Boston, Denver, New Orleans, New York, Florida and Texas. The anecdotes about failed charters are real, but they’re not the norm.
You'll notice that Leonhardt picks cities and states that uphold his argument while excluding others like Detroit, Philadelphia, and Ohio. In addition: I spent a lot of time last year explaining why the vaunted Boston charter sector isn't all it's cracked up to be. I've also documented the mess that is Florida's charter sector. I'll try to get to some of Leonhardt's other examples, but for now: let's talk about Denver.

I'll admit it's one region where I haven't spent much time looking at the charter sector. Leonhardt links to a study that shows some significant gains for charters... although I have some serious qualms about the methodology used in the report. I'm working on something more formal which addresses the issue, but for now (and pardon the nerd talk): I am increasingly skeptical of charter effect research that uses instrumental variables estimators to pump up effect sizes. So far as I've seen, the validity arguments for its use are quite weak -- more to come.

For now, however, let's concede the Denver charter sector does, in fact, get some decent test score gains compared to the Denver Public Schools. The question, as always, is how they do it. Do they lengthen their school day and school year? If so, that's great, but we could do that in the public schools as well. Do they provide smaller class sizes and tutoring? Again, great, but why do we need schools that are not state actors to implement programs like that?

What we want to find are reasons that we can attribute only to the governance structure of charters -- not to resource differences, not to student population differences, but to the inherent characteristics of charters themselves.

And one thing I've found, time and again, is that one of the characteristics of "successful" charters is that they engage in patterns of significant student cohort attrition.

Let me explain what's going on here: this is data for the DSST network, one of the more lauded groups of charter schools in Denver. We're looking at the "class" of each cohort that has come through the entire charter chain; in other words, how big the Class of 2014 was when they were freshman, then sophomores, then juniors, and then seniors. I've done the same with each class back to 2008.

See the pattern? As DSST student classes pass through the charter schools year-to-year, the number of students enrolled shrinks considerably. The Class of 2014, for example, is 62 percent of the size as seniors as it was when freshmen. The shrinkage ranges from 61 to 73 percent over the eight years on the graph.

Where do the kids who leave go? Many likely go back to the Denver Public Schools. Some of those likely drop out, which counts against DPS's graduation rate -- but not the charter schools'. In any case, they aren't being replaced, which I find odd considering how supposedly "popular" charters are.

Some make the case that the larger freshman classes are due to retention: the schools keep the kids for an extra year to "catch them up." Which I suppose is possible... but it raises a host of questions. Do public students have the same opportunities to repeat a grade? Are the taxpayers aware they are paying for this? Why is there still significant attrition between Grade 10 and Grade 11?

Let's look at some other Denver charters and their cohort attrition patterns. Here's KIPP, the esteemed national charter network:

They haven't been running high schools as long as DSST, but the patterns are similar. KIPP's history is as a middle school provider; here are their attrition patterns in the earlier grades:

KIPP's Grade 8 cohorts shrink from 73 to 84 percent of their size in Grade 5. Again: if they're so popular and have such long wait lists -- and if the DPS schools are so bad -- why aren't they backfilling their enrollments? Note too that much of the attrition is after Grade 6. Most Denver elementary schools enroll Grades K to 5. It doesn't appear as if many students come into KIPP looking to move on after only one year; most of the attrition is in the later grades. Why would kids be leaving in the middle of their middle school experience?

Another middle school provider moving into high school is STRIVE:

Grade 8 is between 56 and 80 percent the size of Grade 6. Let's look at one more: Wyatt Academy.

The last class we have data for shrank to 69 percent of its size in First Grade 1 by the time it got to Grade 8.

Let's be clear: cohort shrinkage occurs in DPS as well.

The last year for which we have data was an outlier: the Class of 2018 was 75 percent as big in Grade 8 as it was in Grade 5. For previous years, that figure ranges from 81 to 90 percent. The comparisons to the charters are admittedly tricky: the transition from Grade 5 to 6, for example, is sure to see students moving out of the area or into the private schools, both from DPS and the charters. 

But it's still striking to me that "popular" charters, which are allegedly turning away lottery losers, seem to lose more students proportionally than the "failing" DSP schools.

DPS has a large number of students leave their Grade 9 cohort before Grade 12. Many are dropouts, and that's a serious problem. But why does DPS get slammed for this while the charter high schools are declared "successful" even as they are losing at least as large a proportion of their students as the public high schools?

Again, this is tricky stuff. I'm certainly not going to declare that Denver's charter sector is getting all of its gains from pushing out the lower performers; we don't have nearly enough evidence to make that claim. But neither can we declare definitively, as Leonhardt does, that charter "...success doesn’t stem from skimming off the best." When you lose this many students, particularly in high school, you have to back up and take a more critical view of why some charters get the gains that they do.

One more thing: look at the y-axes on my graphs. The scale of Denver charter school enrollments is nothing like the scale found in DPS. Only recently has STRIVE come around to about 10 percent of DPS's enrollment per class. How can we be sure the gains they make, if any, can be sustained as the sector gets larger?

When charters shed this many kids, there has to be a system that catches them and enrolls them in school. A system that takes them at any time of year, no matter their background. A system that doesn't get to pick and choose which grades it will enroll and when. That system is the public schools; arguably, charters couldn't do what they do without it.

Before we declare charters an unqualified success, we ought to think carefully about whether factors like attrition play a part in helping them realize their test score gains, and what that means for the public school system.

I'll try to get to Denver more this summer. But let's get back to New Jersey next...