"The class sizes are smaller than usual so one on one training can still be provided to every student throughout the lesson. All students are treated as equals and every student will feel welcome from their first day," the group said.

A statement from NSW Police said detectives from the Child Abuse and Sex Crimes Squad established Strike Force Baillieu in July 2017 to investigate reports of historic abuse on three boys, who were under the age of 8.

Seven people were arrested at homes in Katoomba, Canterbury, and Wentworthville at 7am on Monday.

The teenage girl has been charged with eight counts of aggravated sexual assault in company, aggravated kidnapping, and producing child abuse material.

A Katoomba man, 18, has been charged with 42 offences, including kidnapping, sexual intercourse with a child under 10, and common assault.

A Canterbury woman, 20, has been charged with aggravated sexual assault, aggravated kidnapping and committing a serious indictable offence, two counts of common assault, and assault occasioning actual bodily harm.

All three people were refused bail to appear at children's courts on Tuesday.

A Katoomba woman, 26, has been charged with 13 offences, including aggravated sex assault in company, and detain for advantage.

A Canterbury woman, 29, has been charged with five counts of aggravated sexual assault in company deprive liberty, and three counts of common assault.

A Katoomba woman, 58, has been charged with 43 offences, including aggravated sexual assault of a child under 10, sexual intercourse with a child under 10 and aggravated kidnapping. Court listings show an AVO against her has also been sought for the protection of one minor.

A Katoomba man, 52, has been charged with three counts of aggravated sexual assault in company (child under 10), male child abuse material, and using a child under 14 to make child abuse material.

All four were refused bail to appear in various Sydney courts on Tuesday.

Calls to a phone number listed for The Arcade Circus went unanswered on Tuesday morning.