A judge has sentenced the former manager of a high-school bookstore to a year-and-a-half in prison after the 56-year-old woman pleaded guilty to theft and fraud.

The Arizona Attorney General’s Office said Brenda Lynn Busse stole about $120,000 from the bookstore at Tolleson Union High School.

The theft occurred over a five-year period when Busse pocketed cash payments from parents and students, according to state authorities. She then electronically manipulated dates to cover her tracks.

District officials called investigators when they noticed discrepancies in the bookstore’s financial records.

The judge has also ordered Busse to pay restitution, and she will spend four years on probation after her release from prison.