The family of a Brooklyn student who says he was assaulted by a school employee plans to sue the city and the Department of Education.

Matthew Alba claims the assistant dean at P.S. 369 in Fort Greene assaulted him in detention, resulting in a broken arm and bloody chin for the student.

Alba says the assistant dean started verbally abusing him, allegedly saying that he would never amount to anything in life. Alba says that when he defended himself verbally, the assistant dean grabbed his arms and pushed him around, resulting in the injuries.

The family's lawyer says he intends to file a lawsuit for $5 million.

The Department of Education had no comment.