ATLANTA (AP) — A group of former Atlanta educators convicted in a test cheating scandal were locked up in Fulton County jails Thursday as they await sentences that could send them to prison for years.

In one of the nation's largest cheating scandals of its kind, the 11 defendants were convicted Wednesday of racketeering for their roles in a scheme to inflate students' scores on standardized exams.

They include teachers, a principal and other administrators, who were accused of falsifying test results to collect bonuses or keep their jobs in the 50,000-student Atlanta public school system. A 12th defendant, a teacher, was acquitted of all charges by the jury.

The racketeering charges carry up to 20 years in prison. Most of the defendants will be sentenced April 8.

"This is a huge story and absolutely the biggest development in American education law since forever," University of Georgia law professor Ron Carlson said. "It has to send a message to educators here and broadly across the nation. Playing with student test scores is very, very dangerous business."

A state investigation found that as far back as 2005, educators fed answers to students or erased and changed answers on tests after they were turned in. Evidence of cheating was found in 44 schools with nearly 180 educators involved, and teachers who tried to report it were threatened with retaliation.

Similar cheating scandals have erupted in Philadelphia, Washington, D.C., Nevada and other public school systems around the country in recent years, as officials link scores to school funding and staff bonuses and vow to close schools that perform poorly.

Thirty-five Atlanta educators in all were indicted in 2013 on charges including racketeering, making false statements and theft. Many pleaded guilty, and some testified at the trial.

Former Atlanta School Superintendent Beverly Hall was among those charged but never went to trial, saying she was too sick. She died a month ago of breast cancer.

Hall insisted she was innocent. But educators said she was among higher-ups pressuring them to inflate students' scores to show gains in achievement and meet federal benchmarks that would unlock extra funding.

Over objections from the defendants' attorneys, Superior Court Judge Jerry Baxter ordered all but one of those convicted immediately jailed while they await sentencing. They were led out of court in handcuffs.

"They are convicted felons as far as I'm concerned," Baxter said, later adding, "They have made their bed and they're going to have to lie in it."

The only one allowed to remain free on bail was teacher Shani Robinson, because she is expected to give birth soon.

Bob Rubin, the attorney for former elementary school principal Dana Evans, said he was shocked by the judge's decision and called it "unnecessary and vindictive."

Prosecutors said the 12 on trial were looking out for themselves rather than the children's education. Defense attorneys accused prosecutors of overreaching in charging the educators under racketeering laws usually employed against organized crime.

The attorneys for some of the defendants said they will appeal.

Hall served as superintendent for more than a decade, which is rare for a big-city school chief. She was named Superintendent of the Year by the American Association of School Administrators in 2009 and credited with raising student test scores and graduation rates, particularly among the district's poor and minority students.

But the award quickly lost its luster as her district became mired in the scandal, which began to unfold when The Atlanta Journal-Constitution reported that some scores were statistically improbable.

In a video message to the staff before she retired, Hall said: "I am confident that aggressive, swift action will be taken against anyone who believed so little in our students and in our system of support that they turned to dishonesty as the only option."

The months-long trial began in August with more than six weeks of jury selection, and testimony concluded in late February.

District Attorney Paul Howard said it was the biggest and most complex case his office had ever handled. It lasted more than two years and involved hundreds of interviews with school administrators, staff, parents and students.

"Our entire effort in this case was simply to get our community to stop and take a look at the education system," Howard said.

Dessa Curb, a former elementary school teacher, was the one educator acquitted of all charges.

"I've prayed and I believed that this would be my outcome," said a dazed-looking Curb, tears in her eyes.