Headteachers are backing growing calls for pictures of topless models to be banned from newspapers.
The National Association of Head Teachers (NAHT) said it had signed up to the No More Page 3 campaign amid concerns that children can find such images "confusing and embarrassing".
The union is understood to be the first teaching association to lend support to the group.
NAHT general secretary Russell Hobby said school leaders understand the important of protecting children and young people from inappropriate adult material.
"Our members have told us about the problems the easy availability of pictures like these cause, as children, especially very young children, can find such images confusing and embarrassing," he said.
"Most adults recognise the importance of the watershed and online parental controls for computers and game consoles - most also appreciate the need to restrict the publication of pictures like those seen on Page 3 to adult-only publications."