A teacher who molested four boys at a Melbourne Jewish school was sent overseas where he offended again, a court has been told.

David Kramer, 52, has pleaded guilty to five charges of indecent assault and one count of indecent acts with a child over incidents at Yeshivah College in St Kilda East.

The American-born teacher admits to groping the four boys through their clothing between 1990 and 1992.

At his plea hearing on Wednesday, prosecutor Brett Sonnet said Yeshivah's administration had initially declined to stand Kramer down because of concerns for his welfare.

Mr Sonnet said Kramer had admitted some of the accusations, but the college did not act until parents staged a protest outside his house.

The school finally agreed to send him to Israel in 1993, the Victorian County Court was told.

Kramer was jailed in 2008 in the United States for sexual offences against a child in Missouri, before being extradited to Australia last year.

His lawyer Tim Marsh said Yeshivah had covered up his offending.

"There could have been an investigation, there should have been an investigation," Mr Marsh told the court.

"Instead there was a cover-up ... (and) he was quietly shuffled out the back door to Israel."

Kramer is believed to be the first employee of a Jewish institution in Australia to plead guilty to child sex crimes.

He will be sentenced on July 24.