PROVIDENCE — A former Massachusetts schoolteacher pleaded no contest yesterday to three charges of second-degree molestation of a teenage Barrington girl whom he met in an Internet chatroom.

Superior Court Judge Mark Pfeiffer sentenced Christopher P. Westfall, 29, of Sutton, Mass., to seven years in prison. Prosecutor David Prior said that with credit for time spent in jail and in home confinement awaiting trial, Westfall will have to serve a little more than five years at the Adult Correctional Institutions.

He was teaching fifth grade at Sutton Elementary School at the time of his arrest two years ago after the girl’s father told Barrington police that his daughter had run away. She was found that night on Warren Avenue in Swansea, near Route 6.

When police investigated, they determined that the two may have had an “inappropriate sexual relationship.” The girl was 13 at the time.