Abdullah Trad would sometimes have as many as 70 students gathered in the drama room at Condell Park High School to hear his Friday sermons.
They would bring their lunch boxes and leave the playground behind as Trad and other senior students led the voluntary weekly sessions covering whatever Islamic topic they chose to address.
Some weeks it would be a religious teaching about swearing, other weeks about having patience.
"Lying was a big one I used to love talking about because, growing up, I was always taught to be honest," Trad, now 19 and studying teaching at the Australian Catholic University, said.
"We'd always try to deter people from things that were not socially or morally acceptable. And we wouldn't talk about it as though we don't have the problem too, we were going through the same things."
But the type of voluntary lunchtime religious activities that inspired Trad into a teaching career are now under scrutiny amid fears that students are being exposed to violent extremism and the sometimes unsupervised sessions allow for unvetted religious teachings.
On Tuesday, Premier Mike Baird announced an audit into all voluntary prayer groups in NSW public schools, most of which are run by students or outside volunteers.
It was a quick-fire response to revelations that counterterrorism police were investigating a 17-year-old student from Epping Boys High who was allegedly preaching extremist interpretations of Islam during lunchtime sessions.
Assistant Commissioner Mark Murdoch said the investigation at Epping was "not unique" and the profile of young radicals was now as young as 14.
Baird said he had concerns about "a small number of students potentially exposed to violent extremist ideologies".
"Our schools should be, and are, havens of tolerance, places where students can explore the reaches of imagination and knowledge," he said. "We will never allow them to become the setting for extremist ideologies."
However, his announcement highlighted just how little the government knows about voluntary religious prayer groups and activities in schools.
The Department of Education doesn't know how many schools undertake them or what religions are represented – precisely what the audit will seek to establish.
One provider, Scripture Union NSW, runs Christian lunchtime groups in about 100 high schools and 50 primary schools. Many more groups of all denominations are run by students alone or other volunteers.
At Epping Boys High, the school chaplain runs Christian lunchtime groups every Tuesday and Friday while the Islam prayer group meets every lunchtime and is run by Muslim students or a community member.
Religion classes in NSW schools are part of the syllabus and required to be delivered by approved providers, but voluntary prayer groups are different.
Only one paragraph in the department's Religious Education Implementation Procedures is dedicated to rules for "voluntary student activities of a religious nature in schools".
It states that prayer groups are the responsibility of the principal. Since March, principals have been required to obtain parental permission and make sure activities are monitored and outside volunteers pass child-protection checks.
Several Muslim community leaders, parents and educators warned that the lack of supervision and oversight creates a risk of extremist preaching.
"I've been concerned for a long time about what this could potentially lead to," Silma Ihram, an Australian Muslim Women's Association spokeswoman and former school principal, said.
"An audit is just a headcount. It may be helpful but the real issue is the training and the oversight for those teaching Islam – and all religions – in schools."
A parent-led group, Fairness in Religions in Schools, sent letters to the Department of Education almost a year ago with a similar warning, although its primary concern was the excessive proselytising by Christian groups such as Scripture NSW.
FIRIS spokesman Darrin Morgan said the department had not been interested in taking greater responsibility for prayer groups until the suggestion of radical Islam emerged last week.
He said he has met with parents whose children were exposed to homophobic teachings in lunchtime Christian groups and told they or their parents were going to hell.
"An audit is just the tip of the iceberg because the government has enabled this to happen and is only now concerned because of an incident involving Islam," he said.
It is a view shared by some Muslim leaders, who saw Baird's announcement as another knee-jerk political scoring of points at the expense of their religion.
Some questioned how teachers can be expected to identify radicalisation. Lawyer and community advocate Lydia Shelly was automatically suspicious that the monitoring of children is another intelligence gathering operation.
"It just feels like a targeted thing and everything will come under scrutiny," said Sheikh Wesam Charkawi, who works with high school students across western Sydney. "It just keeps happening over and over."
It would be dangerous to shut down prayer groups or over-regulate them, he said.
"You're talking about young men who already feel isolated and besieged in a community. There needs to be space where they can talk about it."
Trad said that was one of the most successful aspects of his popular Friday sermons – they were delivered by the students, for the students.
"We'd be going through the same things as them," he said. "We understood them better."
He made up his own sermons after searching on the internet and occasionally asking for advice from his elder brother, a sheikh, or his father, well-known community spokesman Keysar Trad, he said.
A spokesman for Condell Park High School said a Muslim teacher is always present at voluntary prayer groups.
Trad said some students' sermons would be run past the teacher if there was a worry it might be controversial. Occasionally, some were prevented from speaking.
However, Ihram said it was not enough to leave the responsibility to principals and teachers who "simply are not trained to deal with this".
Baird said the audit would be accompanied by a counterterrorism police briefing for principals.
However, Greens MP John Kaye said the government had been caught out on the back foot over prayer groups.
"They hid behind busy school principals and effectively gave pushy fundamentalist Christian groups free rein in NSW public schools," he said.
Scripture Union NSW chairman Simon Flinders welcomed the audit, which will mostly likely include his organisation, but said it was right to leave principals in charge of administering voluntary activities.
"They aren't all-knowing but they're the people closest to the action on the ground," he said.
Flinders argues that Scripture Union NSW, which trains and vets its own volunteers, offers a better model than simply having students run prayer groups.
The least amount of concern over the workings of voluntary prayer groups seemed to come from parents and students at Epping Boys High, the scene of the counterterrorism investigation.
Several students posted on Facebook that the investigation was "absolute rubbish" and the school environment was inclusive and safe.
Rana Ramlawie, the mother of a boy who attends the Friday sessions, said her son never came home with extremist teachings and the investigation was over false accusations made during a fight between two boys.
Trad said that as long as a teacher kept a close eye on what students were teaching, voluntary prayer groups were hugely important to young Muslim men.
Inspired by his early taste of teaching, he now teaches scripture at three primary schools while completing his degree.
"When I was going through high school, I had a feeling I was kind of just doing nothing, I wasn't really making any difference or helping someone other than myself," he said.
"When I started teaching scripture, there was such a sense of accomplishment. It felt so good."