The girl, a student of class X, was held on charges of murder and produced before a Magistrate court today which remanded her to a juvenile home.
The girl had allegedly thrown Durga, her neighbour, into the well on Monday and the body was found yesterday, police said.
Initial investigation revealed that the girl used to frequent Durga's house and play with her. Some days ago, Durga had told her mother, Santhanalakshmi, that the girl had taken Rs 10 from her handbag.
However, when she came to know that it was the girl who had stolen the money, she asked her parents not to send her to their house.
The girl who was enraged with the child then threw her into the well.