A Sydney primary school teacher has been stood down after flying to Brisbane on the weekend to allegedly meet a 14-year-old girl for sex.

The ABC's 7.30 program captured the arrest of Peter Bosma on Saturday morning at a fast food restaurant where police said the meeting was supposed to take place.

Bosma was completely unaware the girl he had been speaking to via Skype was actually a female detective with Taskforce Argos at Queensland Police.

When he arrived at the restaurant, he walked into a trap.

A detective dressed as a teenager was sitting with her back to the entrance as a team of undercover officers pounced.

Police footage showed Bosma being handcuffed in front of restaurant customers before being driven to the watchhouse.

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The 50-year-old appeared in a Brisbane court on Monday morning charged with one count of using a carriage service to groom a child and six counts of using a carriage service to procure a child.

Bosma did not enter a plea and was granted bail on the conditions that he provided a $20,000 surety and promised not to use the internet.

Offender still on staff at north shore primary school

Bosma was employed as a teacher at Waitara Primary School on Sydney's north shore.

The NSW Department of Education and Communities released a statement on Monday saying Bosma was still on the school's staff.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 6 minutes 43 seconds 6 m Child sex offenders are using social networking to target children, police say

"The Department has taken action to remove him from teaching duty pending the outcome of any court proceedings and or subsequent investigation by the Department," the statement read.

Detective Inspector Jon Rouse, who heads Taskforce Argos, said the case was a timely reminder for parents to keep a close eye on their children's internet use.

"It doesn't matter where you are in this country, there will be child sex offenders using the internet to exploit children," he told 7.30.

"It's very easy for a child sex offender to search social media applications for kids and then directly communicate with them.

"A lot of the applications that kids are using have the capability to be invisible or to lock your profile down but a lot of kids don't do that."

More than 170 child sex offenders arrested in 2014

Mr Rouse has been investigating child sexual abuse for more than 15 years and said his team made more than 170 arrests in 2014.

"Last calendar year, Taskforce Argos made more arrests than it had in any previous year," he said.

Detective Senior Constable Marissa Gnech has the unenviable task of finding and chatting to suspected paedophiles in chat rooms and on social media.

Marissa Gnech is tasked with finding and chatting to suspected paedophiles in chat rooms and on social media. ( ABC 7:30 )

On any given day she could be juggling dozens of conversations in which she pretends to be a child.

"You need to stay up to date with what teenagers are interested in, what music they're into, and what movies they're seeing," she said.

"We usually wait until [the offenders] initiate conversation with us and then we'll chat with them and see where they eventuate from there."

Ms Gnech said the work could be extremely confronting.

"Ultimately [the offenders] want sexual gratification, which may lead to them masturbating via web camera to the child," she said.

"Sometimes, once they've reached that sexual gratification, communication by that offender will cease.

"Other offenders may wish to educate the child about sex, so that may include them giving the child instructions on how to masturbate or sending pornographic images or videos they want the child to watch."

Social media sites to work constructively with police

Eleven-year-old Ella from Brisbane, whose identity 7.30 has protected, became the target of unwanted attention in December when using the Canadian messaging app KIK.

"I was talking to my friends on KIK and I got a message from a man I didn't know," she said.

"He was sending some inappropriate stuff that kids my age shouldn't really be seeing and I told him to stop but he kept on doing it."

Ella blocked the mystery user but still felt unsafe.

"I saw on the news a story about a man coming over to see a girl so I thought I should tell mum and dad because I didn't want anything like that to happen to me," she said.

"So I told mum and dad and we went to the police."

Mr Rouse said tech companies like Facebook only recently began working constructively with police.

He said KIK recently signed up to the international anti-child abuse organisation, the Virtual Global Taskforce.

"That's just social responsibility," he said.

"You've created a platform that is being used by monsters to target children.

"It's not rocket science to say you should be taking some responsibility for that application and assist us in trying to stop that kind of use."

Mr Rouse said parents had the biggest role to play in ensuring a conversation between a child and a stranger online did not progress to sexual abuse in the real world.

"The frontline defence is mum and dad or carer," he said.

"Your role in educating your child about these dangers is critical in stopping it happening at the outset.

"Across Australia and around the world, we have the capacity to investigate these crimes both reactively and proactively, but if we could stop it at the outset through education and awareness then these crimes would just not be happening."