How widespread is teacher-sanctioned cheating?

A USA Today investigation that reviewed three to seven years of data found 1,610 cases where entire classrooms in six states and Washington D.C. made huge, statistically rare gains in standardized test scores over the course of just one year. In some of those cases, the class's scores plunged just as steeply the next year.

The findings raise questions about whether some teachers or administrators are encouraging cheating with impunity. The data also indicates that miraculous-seeming turnarounds in test-score performance get very little critical scrutiny.

Students in each classroom improved on the tests by three standard deviations or more--meaning that they improved at a pace greater than that achieved by 99.9 percent of their peers. Experts told USA Today they were skeptical:

Thomas Haladyna, a professor emeritus at Arizona State University, says test gains of 3 standard deviations or more for an entire grade are "so incredible that you have to ask yourself, 'How can this be real?' " Haladyna says such a spike in scores would be like finding "a weight-loss clinic where you lose 100 pounds a day."

Federal and state education policy increasingly rely on test scores to decide which schools to close and even how much to pay teachers. The paper says that for reasons of cost--as well as on the grounds of simple institutional self-interest--many districts don't investigate big test score gains, even when high-profile examples show cheating does happen. Atlanta Public Schools Superintendent Beverly Hall announced her resignation after allegations of cheating at 58 of her schools.

You can read more about which schools showed questionable test score gains, and their explanations for why their students improved so dramatically over a year.

(Map from the Detroit Free Press via This Week in Education.)