A private school teacher has been hit with a new charge as she potentially faces life behind bars over allegations she sexually abused a 15-year-old student.

St Augustine's Brookvale drama teacher Ella Clements, 24, was charged with maintaining an unlawful relationship with a child as an adult.

The charge is brought against an adult when they are accused of engaging in two or more unlawful sexual acts over any period. 

It attracts a potential maximum penalty of life imprisonment.

Clements is also facing three 'back-up' charges of aggravated sexual intercourse with a child.

Police withdrew a charge of intentionally sexually touching a child.

Clements was arrested on school grounds at the elite college on Sydney's Northern Beaches in September 2025.

The private school charges parents as much as $23,590 to enrol their child in Year 12.

It's understood Clements spent two nights in custody before she was bailed to enter a medical facility in NSW's Northern Rivers region.

She must, at all other times, reside with her family in Lennox Head under supervision, The Daily Telegraph reported.

Clements is yet to enter any pleas to the charges.

She has been ordered to attend Downing Centre Local Court in person on June 4, when the matter is listed for possible committal.

In a statement to parents after Clements' arrest, St Augustine's Brookvale principal Jonathan Byrne confirmed she had been stood down and terminated after the allegations came to light.

'As a parent, I acknowledge an investigation like this will cause anxiety,' Mr Byrne wrote.

'We continue to work with police and relevant authorities and, in the meantime, our focus is on ensuring the privacy and wellbeing of the student and family.

'Please respect that in this instance we are legally limited in what we can share, and have a primary consideration to protect the safety and wellbeing of the student. The judicial process must be allowed to run its natural course.'

It's understood Clements had worked at the school for at least a year before the allegations came to light. 

The Catholic college caters for boys in Years 5 to 12.