While students aren’t allowed to cheat, schools chancellor Joel Klein is offering a special one-month amnesty to teachers and principals who do.

Nonresident employees of the Department of Education who send or previously sent their children to city schools without paying tuition will have one month to come clean and pay what they owe. In exchange, the department will not seek disciplinary charges against them.

Mr. Klein announced the offer yesterday, just a day after the special commissioner of investigation for the city school system released a report detailing a web of falsified documents that the principal of Brooklyn Technical High School, Lee McCaskill, and his wife, a teacher at another Brooklyn school, used to send their 9-year-old daughter to P.S. 29 in Cobble Hill even though they lived in New Jersey.

Mr. McCaskill resigned last week amid rumors of the pending report, and the Department of Education announced earlier this week it is seeking to fire his wife, Cathy Furman.

The highly publicized case sent ripples of concern among other teachers and principals, some of whom have quietly stepped forward to ask about how to clean their slate, education officials said yesterday.

Currently, only three students who live outside the city pay to attend city schools. Tuition costs $5,619 a year for students in kindergarten through sixth grade and $5,419 a year for students in seventh through 12th grade.

Full-time tuition for special education students costs as much as $32,959 a year.

“I want to be clear: This sort of behavior is unlawful; it is not some sort of professional courtesy. It will not be tolerated.” Mr. Klein said yesterday in a letter to school principals. “Every day, in everything that I do, I aim to ensure that the Department of Education adheres to the highest ethical standards,” Mr. Klein said. “New Yorkers count on us to educate the City’s 1.1 million schoolchildren, and we want to make sure that every dollar is spent appropriately.”

Employees who step forward between February 21 and March 21 must provide their updated address information and immediately pay tuition for the current and past years.

After March 21, any nonresident employee who is found to be sending a child to a public school without paying tuition will face normal disciplinary actions, which could include termination of their contract, Mr. Klein said.

The president of the United Federation of Teachers, Randi Weingarten, who previously complained about Mr. McCaskill punishing teachers, said she favored the amnesty period.

“The timing of this act in relation to Commissioner Condon’s report suggests the Department of Education believes that more of its employees fall into the same category as Dr. McCaskill,” she said.

Mr. Klein said he did not believe the abuse was widespread.