The conservative school-choice advocacy organization Thomas B. Fordham Institute published a report claiming that the existence of charters raises test scores in surrounding public schools. The claim is that “a rising tide lifts all boats.” This seems counterintuitive when you think about Detroit and Milwaukee, which are flooded with charters but mired at the bottom of urban districts tested by NAEP.
Now this assertion has been reviewed by a scholar and found to lack validity.
Contact:
William J. Mathis: (802) 383-0058, wmathis@sover.net
Yongmei Ni: (801) 587-9298, yongmei.ni@utah.eduReport About Charters Being a “Rising Tide” Sinks Under Weight of Flawed Data
An NEPC Review funded by the Great Lakes Center
Key Takeaway: Due to data and methods limitations, report fails to prove its claim that higher charter market share is associated with achievement gains for all students.
EAST LANSING, MI (November 14, 2019) – A recent report from the Thomas B. Fordham Institute examines whether average achievement in a school district increases as the “market share” of charter schools rises. The report argues that there is a positive competition effect.
Yongmei Ni of the University of Utah reviewed Rising Tide: Charter School Market Share and Student Achievement, and determined that its findings have limited use in guiding policy and practice, because of the flawed data and methods it employs.
Using a national data set of school districts with longitudinal records (allowing an analysis of each school district’s changes over time), the report found that overall, higher charter market share is associated with statistically significant increases in average reading achievement (but not math achievement). Further, the report finds some positive relationships for specific racial subgroups in districts of certain sizes and geographic locations. The report concludes that charter schools are “a rising tide” that “lifts all education boats.”
Professor Ni explains that these findings and conclusions should be interpreted with extreme caution because of major weaknesses surrounding the data and methods, including the measure of charter market share, the sample selection criteria, and the overreliance on results based on a small number of districts, especially those districts with over 95th percentile of charter market share.
Overall, she concludes, the findings have little use to policymakers because of these issues with data and methods and because the report does not probe beneath the surface. For example, it does not examine possible policy factors that might be associated with charter market share in a given area having a positive or negative association with public school systems. Similarly, it does not consider which practices might benefit charter schools and/or public school systems as a whole.
Find the review, by Yongmei Ni, at:
http://nepc.colorado.edu/thinktank/rising-tideFind Rising Tide: Charter School Market Share and Student Achievement, written by David Griffith and published by the Fordham Institute, at:
https://fordhaminstitute.org/national/research/rising-tide-charter-market-shareNEPC Reviews (http://thinktankreview.org) provide the public, policymakers, and the press with timely, academically sound reviews of selected publications. NEPC Reviews are made possible in part by support provided by the Great Lakes Center for Education Research and Practice:
http://www.greatlakescenter.orgThe National Education Policy Center (NEPC), a university research center housed at the University of Colorado Boulder School of Education, produces and disseminates high-quality, peer-reviewed research to inform education policy discussions. Visit us at: http://nepc.colorado.edu/
Diane Ravitch's blog 
“published a report claiming that the existence of charters raises test scores in surrounding public schools”
It’s just amazing how much bias there is in this movement.
It is UNIMAGINABLE to ed reformers that public schools themselves could have done something or anything to improve.
The only POSSIBLE answer is “charters improved public schools”
If all you see are charters and vouchers, then all you look at are charters and vouchers.
Public schools and students only exist in edreformworld to the extent that they validate ed reform promotion of charters and vouchers. That is their only purpose, their only value.
Imagine how this affects all the ed reform produced research we see- the bias is baked in, and it’s so incorporated no one in ed reform even recognizes it.
Public schools and students don’t have any agency in this world. ONLY charters do. Public schools are the passive recipients of ed reform brilliance – it can’t possibly be that they succeeded without ed reformers, or even IN SPITE of ed reformers.
It’s ludicrous. That they palm it off as “science” is embarrassing.
I don’t mind that they promote their schools – obviously, that’s the political play- just leave public schools and students out of it. It’s insulting to be used as some “status quo” population to push their political agenda.
I’ll just give you and example. Receiving little or no support from the ed reform lobby in Ohio, along with the usual budget cuts, my son’s school has done work on attendance. They did it without consultants and without the support of anyone in Columbus, because Columbus works exclusively for charter and private school students.
Will Fordham claim credit for that? They shouldn’t. They provided no positive value to any Ohio public school. In fact, they work against us.
If ed reformers can’t manage to provide any positive or practical value to students in existing public schools, they could at least have the humility to not claim credit when we manage without their help or support.
Have any public schools anywhere improved without a companion charter marketing and promotion campaign?
If so, why? This is science, right? We’re told. Wouldn’t someone who actually wanted to improve public schools (as opposed to being singularly focused on promoting privatized systems) look at that situation?
I’m reading the ed reform “analysis” of Warrens and Sanders public education plans. Comprehensive plans that include huge proposed benefit to students in public schools.
The entire ed reform echo chamber read only the parts that refer to charters, and discuss only the part that pertain to charters. They effectively “disappear” 90% of US students right out of the box. Our kids don’t even make the initial cut for consideration. Lopped off. As usual.
What do you think the effect is when the entire elite education establishment focuses exclusively on the schools that meet their ideological governance requirements? Good or bad for public school students?
Perhaps we could think about hiring a couple of people in government who actually have some interest in students who attend public schools, apart from how our students can be used to sell their schools, or their “movement”, or their elaborate privatized governance schemes.
YES: “The entire ed reform echo chamber read only the parts that refer to charters, and discuss only the part that pertain to charters. They effectively “disappear” 90% of US students…”
Think tanks are really lobbying groups. Any so-called studies from them are more propaganda than legitimate research. Think tanks are not serious academics. They are spin doctors.
The Thomas B. Fordham Institute is not a think tank. It is a school choice advocacy and lobbying organization
Let’s assume that the political goals of the oligarchy and theocracy are solely to control the 99% and to take the 99%’s money- colonialism.
“The Mackinac Center (Koch) and the Michigan Catholic Conference continue to promote private school choice through a constitutional amendment.”
The states’ Catholic Action Network, VoterVoice.net. which is associated with Catholic Advocacy Network, the U.S. Conference of Catholic Bishops, state Catholic Conferences, prosperity Catholic billionaires, the social Darwinist, Koch Network, ALEC, the regional and national Chambers of Commerce – what agendas do they share?
They sink the good boats, as this recent example from Ohio demonstrates:
https://www.beaconjournal.com/news/20191119/former-akron-charter-school-accused-by-state-of-misusing-nearly-168000-in-taxpayer-dollars
The rising tide will lift all boats — stranding the boats on land because of climate change wrought by greedy corporations.
Fordham here as usual converting whatever dwindling status remaining to it as a serious source to that of press-release-mill for its corporate funders…
Had the original charter concept been left alone, instead of being monetized and weaponized for destroying our public schools, this theory might have held water. Imagine a charter which could take on the kids with the greatest challenges and using small class size and innovative teaching techniques, help them to achieve their educational goals. Those remaining in the public schools would have seen a rise in scores (not that it’s important, just that it’s a stick) because the outliers would have been accounted for outside the regular schools.
But that’s not the purpose of the charter industry.
The original charter concept didn’t serve the theocracy/oligarch agenda so it was abandoned in favor of a system that takes money from the communities for churches and billionaires.