James McManus, 68, changed his plea to guilty on the fourth day of his trial.
He admitted striking the four boys and two girls on the head with his hand, and seizing or pulling the girls' hair.
The incidents occurred at the former Dock Street Children's Home in Carronshore, Falkirk, in the late 1970s and early 1980s.
The trial heard that McManus, of Renfrew, was officer-in-charge at the home and the children were aged between 12 and 16.
Five of the children were assaulted on one occasion and one child was struck on the head and seized by the neck by McManus on various occasions at the home between January 1983 and February 1984.
Allegations that McManus hit children with wooden batons, rendered one child unconscious, pushed a screwdriver in his face, threw water over a teenage girl, and that he caused injuries, were dropped.
Stirling Sheriff Court heard that children at the home were "frightened" of McManus, who weighed 26 stone at the time and would go about his work wearing his Salvation Army uniform.
One witness told the trial: "Mr McManus always seemed to deal with me in a rage.
"He'd grab me and shake me and put me against the wall.
"I don't know what triggered his behaviour. I saw it happen to other kids as well.
"Like everybody else I just feared for my life."
Sheriff Wyllie Robertson deferred sentence on McManus until 28 June for reports.
A former Salvation Army officer has admitted assaulting six young people in his care at a Stirlingshire children's home.