CHICAGO – A comprehensive study released Thursday has finally proven what anecdotal evidence has long suggested: Poorly qualified teachers drag down student achievement.

The first-of-its kind study demonstrated that elementary and high school students – even those in middle-and upper-income families – post higher scores on state exams and are more prepared for college if they attend schools where teacher quality is ranked high.

Low-income and minority children benefit the most from good teachers, the study found. In Illinois’ poorest elementary schools with low-teacher quality, the average pass rate on state tests was 31 percent. But in similar low-income schools with higher-ranked teachers, the rate jumped to 43 percent, research revealed.

The researchers evaluated teachers in Illinois, Wisconsin and Ohio, ranking schools according to a teacher quality score.

In Illinois, that score was determined by five factors: the average college entrance exam score of all teachers in the school; results on the teacher licensing test of basic skills; a national ranking of college attended; years of experience; and number of teachers with provisional credentials.

All of the state’s 3,800 public schools were evaluated.

Chicago Public Schools fared particularly poorly in the study, with three-quarters of the campuses landing on the bottom of the pile in teacher quality. Individual school scores were not released.

National research and individual case studies have long hinted that teacher quality is one of the biggest determinants in student performance. But the new research, completed by the Illinois Education Research Council, is the first time student achievement in Illinois has been directly linked to a school’s teaching corps.


“We now know that all kinds of kids, poor, rich, minority, white are effected by their teacher’s ability,” said Kati Haycock, who heads Education Trust, the Washington think tank that helped underwrite the study. “The research shows that kids who have two, three, four strong teachers in a row will eventually excel, no matter what their background, while kids who have even two weak teachers in a row will never recover.”

The Illinois Education Research Council, housed at Southern Illinois University, conducted the study with the co-operation of the Illinois State Board of Education and Chicago Public Schools. The research was funded through the Education Trust by a grant from the Joyce Foundation.


Overall, the study showed that the state’s poor and minority children are trapped in schools with the least qualified teachers. Nearly 90 percent of low-income schools had teachers with the lowest rankings, the study found. The same held true for schools with mainly African American and Latino populations.

Although urban districts such as Chicago have many high-caliber teachers, it is difficult to attract – and retain – a critical mass. Teaching jobs in inner city schools can be demanding and stressful.

“Obviously, there’s nothing more important than getting the best teachers into the communities that need the most help,” said Arne Duncan, Chicago schools chief. “While we’ve taken steps in that direction, we have a long way to go.”

Duncan said the district has boosted the number of nationally board-certified teachers, from 19 to 500 in the last four years. The district also has recruited career-changers who bring valuable skills such as math and science to the classroom.

He added that the district plans to continue aggressive efforts to recruit the most qualified teachers.


The most startling findings in the report relate to the link between teacher quality and student performance, especially when it pertains to low-income and minority students. And the negative effects multiply the longer children remain in schools with low-performing teachers.

In elementary schools where more than half the students were low-income, an average of 44 percent of students passed math, reading, writing, science and social science exams when the school was filled with low-quality teachers. In poor schools with better teachers, the pass rate jumped to 56 percent.

Even in richer schools, kids performed better if they had better teachers. On average, about 78 percent of students in the highest-income schools with the worst teachers passed state exams. In similar schools with better teachers, the rate jumped to 84 percent.

The achievement gaps grew significantly larger in high schools. In low-income high school where the teacher quality was ranked in the cellar, the average pass rate on state exams was about 14 percent. But in poor schools with a better teaching corps, 33 percent of students passed state exams.

In high schools where the teachers had the lowest qualifications, only 15 percent of students were prepared for college, compared with 50 percent in schools where teachers were more qualified. Researchers used student ACT and state test scores, and grade-point averages to determine readiness.

“The data clearly shows that kids who arrive behind in school fall further behind if they don’t have teachers who can help them move ahead,” said Jennifer Presley, executive director of the research council. “And conversely, we see that these children can perform very well if they have access to the highest-quality teachers.”

Teachers union officials, who were part of a consortium that helped prepare the report, agreed with its findings. But recruiting and retaining quality teachers will require better working conditions, stronger principals and more professional development, they said.

“Just defining what is a good or effective teacher and putting them in a school with high class sizes and low resources do not make for the best educational conditions,” said Lanita Koster, education issues director of the Illinois Federation of Teachers. “That teacher may look like a bad teacher in a couple years.”

(c) 2006, Chicago Tribune.

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Distributed by Knight Ridder/Tribune Information Services.

AP-NY-06-08-06 2026EDT

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