A former D.C. principal allegedly lied about her great-grandson’s home address so he could attend her school for free, avoiding nearly $25,000 in non-resident tuition, according to a civil suit filed Friday in D.C. Superior Court.

D.C. Attorney General Irvin B. Nathan promised in a statement to “vigorously prosecute this serious breach of public trust by a self-dealing school official.”

Barbara Campbell seved two decades as principal of Langdon Education Campus, a public school pre-kindergarten through eighth grade. She left the Northeast Washington school last year.

She is accused of conspiring with two adult relatives — her daughter and granddaughter — to falsely claim that her great-grandson lived in the District. In fact, the boy lived with Campbell in Fort Washington, court documents allege, and he rode with her to Langdon every day during the 2010-11 and 2011-12 school years.

The boy also attended Langdon for the first 13 days of this school year, according to court documents.

Non-residents are allowed to attend D.C. public schools if they pay tuition. Campbell and her family members owe $24,707.90 in unpaid non-resident tuition, according to prosecutors, who are seeking additional damages and penalties that together could exceed $75,000. D.C. law allows the District to collect up to three times the amount of direct damages that the city sustains.

In a telephone interview Friday, Campbell called the allegations unfounded and unfair.

She said that her great-grandson did live in the District with his mother and his grandmother but that the three of them have visited her daily since her husband died in 2009. They spend every night with her in Fort Washington to help her through her grief, she said.

“I should be further along with this grieving because my husband’s been deceased, it’ll be four years in March,” Campbell said. “But I’m not quite there yet.”

Asked how the boy could be a resident of the District if he spends every night in Maryland, Campbell said she has considered the boy and his mother homeless because they were kicked out of their apartment in 2009. “We tried to make the best of the situation,” she said.

The boy is now enrolled in a school in Fort Washington, she said.