"I was so mad I was not focusing on what I was doing," he recalled.
But it was far more than that one incident, said his mom, Melissia Chambers. He choked his younger brother, hit his older sister and hid things from his parents, even stealing from them. They couldn't control him.
"We told him that Mommy and Daddy and his brother and sister, we loved him, but we needed a break from his behavior," she said. "We needed to know that he was safe and we were safe."
A 2008 stay at the University Neuropsychiatric Institute the first of his three visits led to his diagnosis with Asperger's syndrome. His family turned him over to state custody in 2010.
His foster mom, Patti Jiordano, 61, said she has not let Michael dwell on the diagnosis during his more than two years in foster care.
"I tell him he's a nice little boy who thinks a little different," she said. "He has to learn to think right I don't let him use it as an excuse." He receives both weekly counseling and medication, which his family couldn't afford.
Michael credits Jiordano for much of his growth, whether it's learning not to slam doors or practicing how to stay calm with deep breathing.
After Michael moved into her house, she taught herself everything she could about autism by talking with friends who are teachers, and reading books and the Internet. Through trial and error, she figured out what worked for Michael.
The skittish kid who showed up at her house, unable to make eye contact, can now show a stranger a composition book filled with his drawings of superheroes.
"I'll remember Patti all my life," he said. "She's the one that brought me back home."
Michael wants to live with his family again but acknowledges he's gotten used to his new life. His mother hopes to see them reunited by the end of the year.
The Chambers have learned techniques from Jiordano and family therapy that they hope will help Michael succeed at home.
"It was the hardest decision that we ever had to make," his mother said, "but I know now without a shadow of a doubt it was the best decision we ever made."