What exactly did Wayne Ryan do that cost him his job? Every District politician, educator and civic activist ought to be demanding an answer to that question.

What? You don’t know who Wayne Ryan is? The public’s lack of awareness is part of the problem. And the District school system seems to want to keep it that way by apparently allowing a quiet coverup of past fake results on its standardized exams.

Ryan was once the star principal at Noyes Education Campus (K-8) in Northeast. His was one of the faces used to promote former chancellor Michelle Rhee’s education reforms. Recruiting literature featured Ryan’s photo and purported success raising students’ test scores.

Then that pesky controversy emerged over suspiciously high numbers of erasures on some of those exams. Correct answers had mysteriously replaced wrong ones on a large number of test sheets, including at Noyes when Ryan was in charge.

In June came news that Ryan, who had been promoted to a supervisory position, was no longer working for the school system. No explanation has been provided, then or now, and some parents are frustrated about it.

“We heard about it one moment, and then it got brushed underneath. My thing was, is anybody going to investigate this? If not, how do you know it’s not going to happen again?” said Ashaunti Wilson, 26, as she accompanied a friend dropping a child at Noyes on Wednesday.

Wilson withdrew her 8-year-old daughter from the school and moved her to a charter school because of the scandal. “It was just pathetic,” she said. “I like knowing where my child is [academically]. If you’re making her test scores higher, it’s impossible.”

Ernest Butler, 45, who was dropping off his nephew and niece at Noyes, is happy with the school, but he faulted its handling of the testing scandal. “They need to let people know what’s going on, what was the outcome of it. Test scores and grades are very important,” Butler said.

It seems quite likely, to say the least, that Ryan was fired or pressured to quit over falsified test results. A third-grade teacher and a special-ed instructor also lost their jobs.

No details have been provided, and almost nothing has emerged about classes in about 100 other schools with suspect numbers of erasures from 2008 to 2010. Considering that such erasures were first identified as a problem more than three years ago, it’s appalling that the District hasn’t gotten to the bottom of this.

Initial investigations by an outside contractor called Caveon are widely viewed as incomplete. Caveon has admitted it didn’t use all the tools at its disposal. Some District officials concede the city didn’t insist that the contractor do so — while promising that vetting of tests from 2011 and beyond will be more rigorous.

We’re still waiting for results of a second investigation of past irregularities, underway for nearly a year, by the District’s Office of the Inspector General and the U.S. Department of Education. Neither would comment this week.

That lackadaisical approach compares poorly with an energetic probe of a testing scandal in Atlanta. In 2010, after months of foot-dragging by the school system (sound familiar?), then-Gov. Sonny Perdue tapped three veteran investigators to dig into the problem. Their blockbuster report concluded that more than 178 educators, including 38 principals, were involved in cheating at 44 schools.

D.C. officials insist that past problems here weren’t nearly as bad as in Atlanta. But without a full investigation, how can we be sure that current principals or other officials have been held accountable if they previously conspired to falsify test results or winked at those who did so?

It wasn’t reassuring that the school system seemed to be stonewalling again in December. After promising for months that it was about to release test erasure data for 2011, the Office of the State Superintendent of Education decided in December to withhold the names of 54 schools involved.

Tamara Reavis, the office’s director of assessments and accountability, said the office did not want to fan suspicions about any school until after a fuller inquiry by an outside contractor. “It’s the whole innocent until proven guilty idea,” Reavis said.

Cate Swinburn, who in January became the school system’s chief of data and accountability, said the focus should be on the future.

One reason I don’t think we can do much more about 2008 and 2009 is it would be a witch hunt. If you interview a student, a student is not going to remember what happened,” she said. “I think we need to focus on 2011 and then making sure that 2012 is as strong as possible.”

It might be convenient just to pretend these problems never happened. But it’s hardly the lesson we want to teach our children about integrity. The city owes the public a full accounting of whether Wayne Ryan — and possibly other principals — cheated in the past.

Robert McCartney discusses local issues at 8:51 a.m. Friday on WAMU (88.5 FM). To read his previous columns, go to postlocal.com.