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April 20, 2005

Certified teachers get better results than untrained counterparts, new study finds

By Lisa Trei

A new six-year study by School of Education researchers shows that elementary students in Houston, Texas, consistently performed better when they were taught by certified teachers rather than by instructors lacking formal preparation.

Led by education Professor Linda Darling-Hammond, an advocate of teacher certification, the research specifically looked at the effectiveness of Teach for America (TFA), a program that sends graduates from the nation's most prestigious colleges to work in disadvantaged school districts after only a few weeks of training.

The study concluded that TFA recruits do not educate students as well as teachers who have received rigorous methodological instruction and practice. Darling-Hammond has criticized programs such as TFA as "a band-aid on a bleeding sore," and argues that long-term, comprehensive solutions are needed to end educational inequity nationwide.

The results of the study, announced April 15 at the annual meeting of the American Education Research Association in Montreal, Canada, could have important policy implications because some policymakers contend that programs such as Teach for America, which attracts enthusiastic young people to work in the profession, are an effective way to meet some of the requirements of the federal No Child Left Behind Act.

In 2002, then U.S. Secretary of Education Rod Paige argued that schools of education should revamp their teacher-preparation programs to eliminate extensive pedagogy and training requirements. He also said that state certification systems should require teachers to have solid knowledge of their subjects, which Teach for America requires of its recruits.

The study's results are important to many urban and poor rural districts that, when faced with a growing demand for teachers, have hired undertrained people using emergency permits or waivers. Such teachers typically work with low-income and minority students in the most disadvantaged schools, Darling-Hammond said.

"Poor and minority students are most likely to be assigned unqualified teachers and are most likely to be harmed by their lack of knowledge and skills," she said. "The study suggests that investments in well-prepared teachers are critically important to closing the achievement gap and improving learning."

The research paper, co-authored by Stanford graduate students Deborah J. Holtzman, Su Jin Gatlin and Julian Vasquez Heilig, looked at more than 4,400 teachers and their 132,000 fourth- and fifth-grade students. The study assessed achievement gains on six different reading and mathematics tests from 1995 to 2002 and discovered that children who were taught by certified instructors outperformed those who were taught by uncertified teachers or alternatively certified teachers, including TFA recruits. The study noted that TFA teachers improved their performance once they were certified, and did about as well as other certified teachers in helping their students succeed.

"We agree with one of TFA's arguments, that compared to other underqualified teachers, TFA teachers did no worse and, in one case, did better," Darling-Hammond said. "If more TFA teachers stayed in the profession, they would have more impact. But 70 to 92 percent of TFA teachers left within two to three years, so students did not [receive] the benefit of teacher certification."

Teach for America responded to the study with a critique on its website ( On April 18, TFA's president, Wendy Kopp, commented in a Stanford Daily editorial that the study was "flawed," that its sample sizes were questionable and that the research was released before it was subject to an independent review.

Darling-Hammond said Kopp failed to read the study thoroughly because larger sample sizes were published in the appendix and added that the work was peer reviewed before it was submitted to a journal where it is awaiting further review. "There is no venom in the article; it pains me that [TFA's] response is so vituperative," Darling-Hammond said. "The finding is that it makes a difference for all teachers, including TFA teachers, to be certified. The major policy implication of the study is that training does matter."

The reviewers included two regents' professors at Arizona State University: Gene Glass, a leading quantitative methodologist, and David Berliner, an educational psychologist. Peter Youngs, an assistant professor at Michigan State University, and Ed Fuller, an adjunct professor at the University of Texas-Austin, commented on the paper when Darling-Hammond presented it at the American Education Research Association's meeting last week.

Berliner, an outspoken critic of TFA, said Darling-Hammond's research was evenhanded. "The data do speak for themselves," he said. "TFA is really bad for America. What they're doing is providing mediocre teachers for the poor. It's missionary work: If [TFA teachers are] not prepared, they can do more harm than good."

In a response to Kopp's editorial, Darling-Hammond wrote that it is important to look beyond specific programs such as TFA to ask the bigger policy question: "Rather than pitting under-prepared teachers against others in comparisons of effectiveness, how can policies provide well-qualified teachers to low-income students of color?" She pointed to urban schools—such as East Palo Alto High—that have been staffed with well-prepared teachers who remain in their jobs because they get decent pay and working conditions. "While a band-aid on a bleeding sore is helpful in a crisis, healing wounds of inequality and poverty is also a policy problem worth solving," Darling-Hammond wrote. "This continues to deserve our attention."



Lisa Trei, News Service: (650) 725-0224,


Linda Darling-Hammond, School of Education: (650) 723-3555,

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