The present article explores home-school relations by analyzing how Swedish teachers and parents negotiate responsibility for children's education and rearing through school letters. It draws on participant observations using a video camera in families, interviews with parents, and analysis of school letters written by teachers to parents. The division of public and private responsibility for children is negotiated in terms of expertise. Teachers position themselves as "educational experts", and are able to prescribe how parents are supposed to be involved in children's education. Teachers construct parents as "rearing experts", and ask them to take responsibility for their children's behavior in school by disciplining them at home. The prescribed parental subject is adopted by parents, particularly mothers, as they position themselves as involved parents. (Contains 2 notes.)