A school house mistress jailed for sexually abusing six boys has been granted bail after a court quashed her conviction and ordered a retrial.

The 43-year-old appeared in the New South Wales Supreme Court in Sydney on Thursday, sitting as the Court of Criminal Appeal.

The crown did not oppose her bail, which carries significant restrictions regarding her movements around children.

Referred to as 'CJ' by the court, the woman was jailed in March 2011 for a minimum of five years over 21 sex offences allegedly carried out a school in 2009.

The alleged offences included fellatio and penile vaginal penetration with boys aged 11 and 12, at sites including the school sick bay, in her flat and on camping trips.

In one incident when five boys were in a tent, she was naked and asked: "Does anyone want a blow job?".

One victim later said the woman had pressured the boys, saying: "Come on, let's go, don't be a puss", and he had "felt like a wimp" until he agreed to oral sex.

On Tuesday, the appeal court quashed her conviction and ordered a retrial, which is not expected to commence before 2013.

She has served about 16 months in jail.

The woman must be of good behaviour, reside at her mother's home, report to local police once a week and not go within 40km of the school where she once worked.

She is also prohibited from being within 100m of a school or public place where children congregate unless accompanied by her mother or her legal representative.

The court ordered she also attend monthly doctor appointments for ongoing medication and counselling and not approach any crown witness in the retrial proceedings.