The state's provider of primary school ethics classes is making an aggressive push for parents to sign up for the scripture alternative ahead of the new school year.
Primary Ethics has almost 100 screens at train stations across Sydney advertising the classes, as well as a short television commercial.
The interactive signs pose the question: "Mum, why is it OK to kill cows and sheep but not to kill whales?"
Ethics, the ad says, "teaches kids how to think not what to think".
The organisation's chief executive, Teresa Russell, says they are aiming to raise awareness, recruit volunteers and source donations.
"Even though the program has been going for four years, parents don't know that ethics is an option for children who don't go to scripture classes," she said.
 
Primary Ethics TVC 261113 from Primary Ethics on Vimeo.
Primary Ethics, a not-for profit organisation formed by the St James Ethics Centre, is the state' sole provider of public school ethics classes.
The classes, which are offered as an alternative to special religious education, now reach more than 20,000 students across the state thanks to almost 1500 volunteers.
"We need more teachers because we're in 327 schools and we need to be in 800," Ms Russell said. "The main thing we are looking for is people who are interested in teaching ethics to kids. We can't have people who are afraid of children or don't like them.
"Our curriculum is written so that the average punter can pick it up after training and walk into a classroom, provided they've got that affinity and rapport with children."
The advertising signs, displayed at key transport hubs including Bondi Junction, Chatswood and Parramatta, were provided free of charge by sponsors.
The 30-second television commercial, which asks viewers to "help us create the next generation of ethical Australians", was produced and aired as a donation from Nine Entertainment boss David Gyngell.
Murray Norman, the general manager of Presbyterian Youth, helps to organise and recruit Christian scripture teachers across NSW. He said the scripture providers tend to advertise within their church communities and in Christian media but he saw no problem with Primary Ethics appealing to the public.
"Primary Ethics is providing a service in the schools and they have the right to advertise and promote what they are doing to attract teachers just like the religious providers have the same right to do," he said.
There are currently more than 10,000 Christian scripture teachers across NSW and Mr Norman says the demand depends on the school community.
"We have strong churches in some areas and we can definitely meet the demand but we have got some places where we are looking for teachers," he said.
