The stories out of Georgia’s largest city have been almost unbelievable, and yet the appalling tale they tell is apparently true.

The entire Atlanta public school system has been exposed by a state investigation to have been altering the results of standardized student achievement tests for years.

The upgraded test results have garnered the system and its leaders state and national recognition — and in some cases, bonuses — over a full decade.

According to reports, the behavior, which was clearly unethical, in some cases may be criminal as well, perhaps leading to formal charges being brought against top system officials.

The state report, released recently by the office of Gov. Nathan Deal, a Republican, names 178 educators, including 38 principals, as participants in the cheating scandal.

The practice of altering scores was found in 44 of the 56 city schools that investigators included in their probe, which lasted almost two years.

Teachers told investigators that “a climate of fear” was imposed by their superiors, ranging all the way up to the office of recently retired Superintendent Beverly Hall and her aides.

Supervisors “ignored, buried, destroyed, or altered complaints about misconduct, claimed ignorance of wrongdoing and accused naysayers of failing to believe in poor children’s ability to learn,” the Atlanta Journal-Constitution said, adding that Hall has denied knowledge of the practice.

But area superintendents “silenced whistle-blowers and rewarded subordinates who met academic goals by any means possible,” the newspaper said. Officials also destroyed or altered documents revealing the practice.

No matter what the legal outcome, the story raises serious questions about the vulnerability of such tests to this or other types of cheating.

Some have said the scandal shows that testing and demands to show rising levels of achievement from year to year are too significant to teacher and district ratings, levels of financial support and individual compensation.

But even if that’s true — and that debate isn’t over by any means — blaming the system ignores the widespread lack of ethics among people that citizens expect to display the highest levels of personal and professional honesty and responsibility.

These “professionals” not only have apparently lied to state officials for their own profit — but they have also lied to city parents and their children about levels of achievement, something that may well have done lasting harm to students’ academic prospects and opportunities for employment.

Those proved to have been involved should — at a minimum — never be allowed to hold a job in education again.