Investigators are stumped as to why a 32-year-old woman allegedly pretended to be a homeless teenager to enroll in an upstate New York high school. 

Michaelann Goodrich was arrested last week for allegedly posing as a 15-year-old named Riley Madison and attending classes in the Cairo-Durham School District, as Albany, N.Y., news station WNYT reports.

“She could’ve gone in numerous different ways to obtain a degree, and we actually found out through the investigation and that she has a high school diploma,” Joel Rowell, Greene County Sheriff’s Department senior investigator, told WNYT. “So that just leads to our investigation to try to figure out what exactly her motive was for attending school.”