The Stamford Advocate reports that the lawsuit filed April 23 in Superior Court in Bridgeport names the Stamford Board of Education and the city of Stamford as defendants.
The suit alleges that the principal and staff at Roxbury Elementary School breached their obligation to keep the boy safe and violated state law by failing to report the pencil stabbing to the state Department of Children and Families.
The suit says the victim suffered permanent physical and psychological injuries.
The family is seeking damages totaling more than $15,000.
A school district spokeswoman declined comment, citing pending litigation.