Fewer than half the states routinely analyze suspicious numbers of erasures on standardized school tests, a key method of detecting cheating by teachers or their bosses.
A survey by USA TODAY of state education agencies found that 20 states and Washington, D.C., did erasure analysis on all pencil-and-paper tests required during the 2010-11 school year under the federal No Child Left Behind education law.
That means nearly 45% of the annual reading and math exams this year were scored without analyzing erasures.
The analysis looks for unusual rates of answers erased and changed from wrong to right. Statisticians consider it a key indicator of whether educators are correcting students' answers in order to boost their schools' scores.
Erasure analysis called 'common sense'
"It's a very powerful tool to assist states in identifying patterns and determining if something is amiss," says Ron Tomalis, Pennsylvania's secretary of Education. His department is investigating 89 schools flagged for high erasures in 2009. The department is also analyzing erasure reports for 2010 and 2011. "It is a signal to people in the field that the manipulation of test data will not be tolerated."