ANTIOCH, Calif. -- The family of an 8-year-old California boy filed a claim Tuesday alleging the boy's third-grade teacher duct-taped his mouth shut and that another teacher punished him by placing a chair over him and sitting on it in separate incidents earlier this school year.

Another student's hands were duct-taped by Antioch Charter Academy II teacher Michelle Mankewich in November, the claim alleges.

All four Antioch Unified School District employees who witnessed or learned of the November incidents failed to perform their mandated reporting duties and notify authorities about them, the claim alleges. The charter school principal -- the mother of one of the teachers alleged to have abused the boy -- conducted an internal investigation that found no wrongdoing.

"These are highly inappropriate forms of restraint on a student. It's abusive. I'd call it child abuse," said Larry Cook, the Walnut Creek attorney who filed the claim. "There's got to be other ways to control kids in a classroom."

The Antioch boy, through his mother, Luvy Torres, filed the claim against the Antioch district; the charter school; The Learner-Centered School Inc. (the nonprofit that operates the school); Mankewich, teacher Marianne Dubitsky, teacher Julie Fajeau and Principal Jeannie Dubitsky, alleging they violated his constitutional rights, assaulted him and discriminated against him, among other charges. The boy's family seeks more than $10,000 in damages.

Calls and emails to the school, nonprofit and individual employees were not returned Tuesday. The school is on break this week.

Antioch Unified Superintendent Donald Gill, who learned of the claim Tuesday, said the charter academy is independent of his district, which nevertheless has general oversight responsibilities to ensure academic and fiscal accountability. The school has its own separate board of directors that manages funding, staffing and school policies.

The boy, diagnosed with a learning disability related to auditory processing, received special-education resources at the school. But the alleged abuse took place in a mainstream combined classroom of first-, second- and third graders where Mankewich, Marianne Dubitsky and Fajeau shared teaching duties.

The claim says that on the morning of Nov. 27, Torres was asked by the mother of another student whether she knew her son and other students had been duct-taped in class by Mankewich the previous day. Torres confirmed with her son that day that Mankewich took a roll of duct tape from her desk drawer and placed strips of it over his mouth, as well as on the hands of another student in class, according to the claim.

"She just came up and duct-taped me," the boy said in a December CBS5 News interview. The family was not commenting Tuesday, Cook said.

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