The General Accounting Office said retiring teachers can spend a single day – their last working day – as a janitor or a clerk, pay as little as $3 in Social Security taxes, and collect an average $93,000 or more in spousal retirement benefits over the rest of their lives.

Jeri Stone, executive director of the Texas Classroom Teachers Association, said her organization not only encourages Texas teachers to take advantage of the loophole, but also lobbies against the federal provision that was intended to prohibit public employees from collecting both.

"We're not unhappy that the loophole exists," Ms. Stone said.

The report offers no estimate of the extent of the problem nationwide, focusing only on Texas and Georgia. Of 4,819 cases studied, all but 24 were in Texas.

The cases reviewed by the GAO primarily involve Social Security spousal benefits, which are intended for the wives or husbands of workers covered by Social Security who have little or no income of their own.

Under federal law, retirees with state or local government pensions cannot receive full spousal Social Security benefits, even if they would otherwise qualify – the so-called Government Pension Offset. A provision of the law, however, allows those additional benefits to be collected if a retiree's final working day is spent in a job covered by Social Security.

The pension offset applies to government employees in about a third of the 2,300 state and local retirement programs nationwide.

"I requested the GAO report because I was concerned that this loophole was being used to compromise the intent of the law, worsen Social Security's long-term financial challenges, or could have other unintended consequences," said Rep. E. Clay Shaw, R-Fla., chairman of the House Ways and Means Social Security Subcommittee.

"The apparently growing use of the loophole is only a symptom of general concern about whether the GPO itself is fair."

The loophole arrangement works this way: A retiring teacher can transfer to a school in a Texas district that is covered by Social Security. By working as little as a single day at the new job – most often as a janitor, a clerk or a food service employee – a teacher can retire with the full spousal benefit.

The GAO calculates that this extra benefit, about $4,800 per year, will be collected by the 4,795 Texas teachers for an average of 19.4 years.

For some school districts, the hiring of these retiring teachers has been a bonanza. According to the GAO, some Texas schools are charging as much as $500 in "employment application fees." One unidentified Texas school, the report said, earned $283,000 in such fees.

In addition, the GAO said, several Texas community colleges and at least one university have pursued these one-day employees. A GAO official declined to identify the Texas schools involved.

Some Texas school districts are actively advertising their involvement in securing the extra benefits. For instance, the Coleman Independent School District, just northeast of San Angelo, advertises its "Temporary Employment Program" on its official Web site.

Says the site: "Coleman ISD employs people for temporary employment [sometimes as little as one day] in a non-professional role. This may include custodial work, cafeteria work, clerical work, classroom aide, etc. If employed by Coleman ISD in a temporary role your compensation for the work will have deductions for the Teacher Retirement System and for Social Security."

The fee for this service, according to the Web site, is $200. The Coleman ISD official cited as the contact for the program did not return calls.

Daniel Bertoni, GAO assistant director, said the loophole investigation began as a tip from the government's FraudNET hotline, but no criminal activity was uncovered.

"Still, it proved to be a public issue that needed to be addressed," Mr. Bertoni said.

Ms. Stone, of the classroom teachers association, said she is glad that the report has raised the issue of the pension offsets, which she and her member-teachers believe are unfair.

Some teachers say they have worked at previous jobs and have paid into the Social Security system but cannot receive a benefit. Others say they would have received spousal benefits for doing nothing at all if they hadn't worked for the government.

"They're surprised, in fact, when they learn that they can't get a benefit. They believe it's unfair," Ms. Stone said.

Bill Passmore of the Richardson Retired Teachers Association said he and other members receive calls every year from retiring school district employees who want information about the loophole. However, he added, there wouldn't be a need for the loophole if the Government Pension Offset and other prohibitions were eliminated.

"The Texas Retired Teachers Association has as one of its legislative goals this year to repeal those rules," Mr. Passmore said. "We feel like they're unfair to teachers."

Staff writer Kristine Hughes in Dallas contributed to this report.