Preston Green said that if charters are allowed to grow without safeguards, students could end up with fewer choices.
A University of Connecticut professor warned that the unchecked growth of charter schools could lead to something similar to the subprime mortgage bubble.
Professor Preston Green has called for safeguards to be set up to prevent the charter bubble from bursting.
Charter schools have been growing fast, and state leaders, including Governor Dannel Malloy, have advocated for more of these schools to be built.
Green said it might be time to put the brakes on.
"I am not taking the position that charter schools are inherently bad," Green said. "I understand that parents and children want to have education choices. What I want to see happen is a situation where we can guarantee that those choices are good."
Green teaches at the education school at UConn and recently published a paper with several colleagues looking at the issue of charter school growth. Charters are like traditional public schools, except they're free from many regulations that are imposed on school districts.
Charters operate mostly in urban areas, where there's high numbers of black and Latino students. As dissatisfaction with the local schools grows, so does demand for more charters, and this has fueled calls to make it easier to open more of them.
But Green said scandals across the country show there should be more regulation, not less.
"State and local governments have to take a strong stand to ensure that if we're going to grow charter schools, we have provisions in place to prevent abuse," Green said.
Because some charters are profit-making, Green said this can be an incentive to engage in practices that are good for the books, but bad for kids. Connecticut currently does not allow charter management companies to be for-profit.
However, if charters are allowed to grow without additional safeguards, Green warned that students could end up with fewer choices because of how selective charter schools can be. This selectivity could create an environment where students who struggle the most are left without any options, except a poor-performing public school. Minorities, students with disabilities, and English language learners could be hit the hardest.
In a response posted on its website, the National Association of Charter School Authorizers, calls the article "misleading" and says the authorizing of charter school is based on three principles: Making decisions that protect the interests of students and the public; hold charter schools accountable; and help charter schools have the freedom to innovate.
Editor's note: An earlier version of this story indicated that charters are often run by for-profit companies. Connecticut law prevents charter schools from being profit-making.