Kevin Powell assaulted the children, of which one was as young as five, between 1978 and 1979 at various locations in Bilston.
One attack happened in a public toilet and another in a house.
Powell, aged 48, of Alice Street, Bilston, was found guilty of four charges of indecent assault at Wolverhampton Crown Court in May.
Yesterday he was given a two-year jail sentence, suspended for two years.
Speaking after the hearing the family of the victims described the sentence as 'a disgrace'
The court had been told how Powell was brought to the attention of the police in December 2010.
One victim told his wife years after the attack and went to the police.
It emerged during the case that Powell had been a bus driver but had lost his job as a result of his conviction.
Defending him, Mr Jas Mann, said: "This is something which happened 35 years ago. He has got on with his life and this has never been repeated. It was a life time ago and he rehabilitated himself. He has worked hard all of his life and these actions were carried out by a young man of 12."
Judge Michael Challinor said: "This was an offence committed by a child of 12 and as a result his role is significantly lesser. This puts it in a lesser category for sentence.
"You were very young and very immature when you committed this offence."
As Powell avoided going to jail the mother of one of the victims hit out at the sentence.
She said: "It's a disgrace. I'm not happy with it. I was expecting him to get at least five years."