Who would have ever imagined that Pearson would be at the epicenter of the final quake ?
By MORGAN SMITH
In 2006, a math pilot program for middle school students in a Dallas-area district returned surprising results.
The students’ improved grasp of mathematical concepts stunned Walter Stroup, the University of Texas at Austin professor behind the program. But at the end of the year, students’ scores had increased only marginally on state standardized TAKS tests, unlike what Mr. Stroup had seen in the classroom.
A similar dynamic showed up in a comparison of the students’ scores on midyear benchmark tests and what they received on their end-of-year exams. Standardized test scores the previous year were better predictors of their scores the next year than the benchmark test they had taken a few months earlier.
Now, in studies that threaten to shake the foundation of high-stakes test-based accountability, Mr. Stroup and two other researchers said they believe they have found the reason: a glitch embedded in the DNA of the state exams that, as a result of a statistical method used to assemble them, suggests they are virtually useless at measuring the effects of classroom instruction.
Pearson, which has a five-year, $468 million contract to create the state’s tests through 2015, uses “item response theory” to devise standardized exams, as other testing companies do...