ATLANTA (AP) — A new state report shows that the number of schools with unusual erasure patterns on standardized tests plummeted last year after a massive cheating scandal that led to tighter exam security across the state.

The Governor's Office of Student Achievement told the state school board Thursday that just three schools were flagged as "severe concern," meaning they had 25 percent or more of classrooms with a high number of erasures. That's compared to 74 schools in the severe category in 2009.

In all, 189 schools were flagged, though most had low patterns of erasures. The schools must conduct investigations and report back to the state by May.

A similar analysis of 2009 tests led to a state probe revealing widespread cheating in 180 Atlanta schools.