The sad story of educators caught manipulating standardized exam scores has focused attention on one type of “fallout” from the testing explosion that has swept across the nation’s classrooms in the past decade. Federal and state lawmakers are scrambling to incorporate lessons from Atlanta as they work to overhaul testing policies in the face of an increasingly powerful assessment reform movement.

So far, policymakers have grasped only the most basic message from the Atlanta scandal: sharp score gains may not be what they first appear to be. Most state departments of education have hired “data forensics” firms to examine test answer sheets. Using computers, they now search for unusual numbers of erasures or odd patterns of score gains. Many have become more willing to pursue reports by whistleblowers.

The ensuing investigations confirmed cases of cheating in 40 states, the District of Columbia, and schools run by the U.S. Department of Defense. Adults manipulated test scores in more than 60 ways, from shouting out correct answers to barring likely low-scores from enrolling. The Atlanta scandal is just the tip of a test cheating “iceberg.”

In the wake of Atlanta, many jurisdictions stepped up test security. However, tougher exam administration policing has not made test cheating disappear. In just the past few months, new examples have surfaced in Pennsylvania, New Mexico, Ohio, Louisiana and several other states.

Understanding the widespread “gaming” of standardized exam results requires addressing its root cause. Nearly four decades ago, social scientist Donald Campbell forecast today’s scandals. He wrote, “[W]hen test scores become the goal of the teaching process, they both lose their value as indicators of educational status and distort the educational process in undesirable ways.” The horror stories in Atlanta and many other communities are case studies of what is now called Campbell’s Law.

Many policymakers still ignore the most important lesson to be learned from Atlanta. Cheating is an inevitable consequence of the overuse and misuse of standardized exams. Federal, state and local testing policies put intense pressure on teachers, principals and other administrators. They create a climate in which educators believe scores must soar “by whatever means necessary,” as the Georgia Bureau of Investigation concluded.

It is hardly surprising that more school professionals cross the ethical line. Across the nation, strategies that boost scores without improving learning are spreading rapidly. These include changing answers, narrow teaching to the test and pushing out low-performing students. These practices are immoral, unethical and, in many cases illegal. But they are completely understandable.

The test score fixation takes time away from broader and deeper learning, leaving students inadequately prepared for college or careers. Simultaneously, it inflates test results by making it appear as if there is real academic growth when there may be none.

To eliminate cheating, reliance on standardized exam results for high-stakes educational decisions must end. Test-driven schooling cheats students out of a high-quality education. At the same time, it cheats the public out of accurate information about public school quality.

Until assessment policies are overhauled, Atlanta will stand out as the ugliest example of a continuing national epidemic.