Charter Schools Have Positive Impact on Nearby Schools, Study Finds

Published March 14, 2018

Charters have a “spillover” effect on nearby traditional government schools, and the closer the proximity to a charter school, the greater the positive effect on the students in the nearby schools, Sarah A. Cordes, assistant professor of policy, organizational, and leadership studies at Temple University, reports in “Charters and the Common Good: The spillover effects of charter schools in New York City,” published by EducationNext in spring 2018.

Cordes studied more than a decade’s worth of student achievement data for 876,731 students attending 584 elementary schools in community school districts in New York City (NYC) with at least one charter school serving children in similar grades.

“These findings shed new light on the public debate over the effects of charter schools on non-charter students,” Cordes writes. “Rather than sapping resources and putting students at district schools at a disadvantage, the data in New York City show that students do better when charters open nearby. In particular, students at co-located district schools, where their school shares a building with a charter school, experience the most sharply positive spillover effects. Importantly, the effects of co-location appear to be specific to charter schools, as students in district schools that are co-located with other district schools do not experience similar performance gains.”

Policy Implications 

Cordes says the policy implications of her research are twofold.

“First, charter schools appear to have modest positive effects, or at the very least, no significant negative effects on student performance at district schools nearby,” Cordes writes. “This suggests that rather than capping the number of charter schools, it may be beneficial (and certainly not harmful) to allow for further expansion in NYC. Second, my results indicate that controversial co-location practices may actually be a good policy for both charter and district schools in NYC.”

The Closer, the Better

Cordes told School Reform News New York City policies make her research particularly meaningful.

“New York City has smaller districts within the larger districts,” Cordes said. “It was a unique opportunity that I had in New York because it’s one of the few cities that does co-location.

“I found that charters seemed to be increasing the performance of traditional public school students, and the effect was bigger when the charter school was co-located,” Cordes said. “The impact in the co-located school was relatively sizeable given that this was not an intervention within the schools, just going on without.”

More Spending Per Pupil

Cordes says the presence of charter schools enables traditional government schools to spend more money per pupil. 

“New York City is rather unique in that [there is] school-level financial data,” Cordes said. “I wanted to look not just at the effects of charters on student performance, but the financial effect as well.

“I found that after charter schools opened, there was actually more spending per pupil at the school level for [traditional government] schools that were located near a charter school,” Cordes said. “The reasons for that, I suspect when I look at enrollments, is the enrollments in those schools declined slightly but not drastically enough to reduce the number of teachers. The school couldn’t really cut [costs], and it’s getting spread out over a smaller number of students. New York has some very specific funding for schools, where the budget can’t change much from year to year.”

‘Competition Is a Dirty Word’

Aaron Smith, an education policy analyst at Reason Foundation, says it makes sense increasing competition improves all types of schools.

“Competition is a dirty word in education, but it shouldn’t be,” Smith said. “When school districts have a monopoly over enrollment, they have little incentive to innovate and respond to the needs of families. Options such as charters, open enrollment policies, and education savings accounts give parents the ability to hold schools accountable if they fail to meet their needs, and it shouldn’t be surprising that educators respond to parent-driven accountability by getting better. Just as competition has improved our standard of living in every other facet of life, it can also help improve outcomes in education.

“The results are encouraging, and we’ve come a long way in this respect, but we also need to maintain perspective, as there’s still much work to be done before all families have robust options,” Smith said. “Only then will we see exactly how beneficial competition really is.”

More Charters, Larger Impact?

Cordes says additional data will provide further insights into the effect of charter schools on neighboring traditional government schools.

“There’s been some research out there that indicates that charters take a while to get off the ground and become effective, and you need the longer period of data in order to assess that,” Cordes said. “My data captured ten years of charter schools, and they didn’t really start ramping up until two or three years after I began collecting my data. In the period I was studying, only about 5 percent of kids were in charter schools, not a huge part of the market.

“I would like to do work in other cities where charters are a larger share of the market,” Cordes said.

Ashley Bateman ([email protected]writes from Alexandria, Virginia.


Sarah A. Cordes, “Charters and the Common Good: The spillover effects of charter schools in New York City,” EducationNext, Spring 2018: