Double-digit test score gains in a single year aren’t the norm for a school, but also aren’t uncommon — inviting celebration, scrutiny and attempts to explain the sudden boost. Likewise, sharp declines can lead to a school’s closure, or the dismissal of all of its teachers.
It might be hasty, however, to draw conclusions about what’s behind such spikes or nosedives, warns Dale Ballou, a researcher at Vanderbilt’s Peabody College of Education in Nashville. Even large score bumps can mean that the school just got lucky.
“There’s a lot of sources of variation,” Ballou said. “You’re not going to be able to identify when it wasn’t due to chance.”
That view can be troubling in a climate of high-stakes testing in which standardized assessments are the primary measure of a student’s academic skills, knowledge and growth — as well as the effectiveness of the educators who taught the student.
In scores released in July by the Tennessee Department of Education, Shelby County saw 36 schools post double-digit gains and eight with double-digit drops. The state-run Achievement School District had six of its 15 elementary and middle schools score double-digit gains in math, with one school posting a double-digit decline. In Metro Nashville Schools, a much smaller percentage of middle and elementary schools — 12 of 129 — saw similarly large gains in math, and four posted double-digit declines.
In Memphis, Springdale Elementary earned the distinction of being Tennessee’s only school to go off of the priority list of the state’s 5 percent of worst-performing schools and move straight onto the state’s reward list of the top 5 percent of schools for academic achievement or annual growth.
Springdale, located near Rhodes College, scored 5 on its TVAAS, which is the highest score awarded by the state for growth. It boosted its math proficiency scores by 27 percent to almost 42 percent, its reading scores by 2 percent to 19 percent, and its science proficiency scores by 30 percent to almost 55 percent.
While it takes several years of consistent data to draw an accurate picture, Ballou says a single-year increase in scores can mean that a school is, in fact, on the right track. “You don’t want to overreact to one year’s good news, but you don’t want to never believe it either,” he said.
At the same time, test scores can change for better or worse because of factors that often are out of school leaders’ control, such as the number of new students or the percentage of students changing schools.
Teacher turnover also can cause dramatic variations and can occur for many reasons. For instance, good teachers may leave if they believe that administrators don’t support them, and bad teachers might quit or be reassigned. Sometimes, teachers retire coincidentally in waves.
Also, tests simply can’t reveal everything that happened in a single school year.
“These are relatively short tests,” Ballou said. “Maybe the test asks a lot of questions that you specifically emphasized in your class … or the opposite can happen, and you’re unlucky.”
Dramatic gains sometimes have been traced to cheating in other states, most notably in Atlanta where public school educators received stiff sentences in April after being convicted in a conspiracy to inflate student scores on standardized tests. In Tennessee, however, test score variation won’t necessarily trigger an investigation, says state Department of Education spokeswoman Ashley Ball.
“Our best test security mechanism is human intervention,” Ball said. “Our testing office is in constant communication with district testing coordinators before and throughout the testing process, answering questions and reminding them of best practices.”
She added that erasure analysis — investigating test security at schools where many answers were changed on paper tests — has been a way to support schools in ensuring testing security.