Guidance on teaching online safety in schools to make children more resilient to catfishing, fake news and other online harms has been announced by the education secretary.

The guidelines will combine teaching on relationships, citizenship and computing to help students understand the technology behind targeted advertising, false profiles and other digital issues.

Damian Hinds, the education secretary, said: “It’s based on the premise that if you really understand the technology, you’re less likely to get used by the technology. Then even when the technology changes, your knowledge is somewhat future-proof.”

The guidance, which is non-statutory, will advise schools to teach students about how URLs are made and what an IP address is, as well as how companies make targeted adverts through tracking behaviour and how someone can create a fake profile.

“At the most elemental level, it’s about understanding what people’s motivations are – why people behave differently when they’re behind a computer screen and why companies want to get your data for commercial advantage,” Hinds said.

The education secretary, speaking at an NSPCC conference about child online safety, said technology companies should not wait for legislation to be implemented to take action to protect children online.

He stressed they should make it easier for parents to exercise control over what their children can see online and that child-safe modes should be the default setting in many cases.

The culture secretary, Jeremy Wright, also expressed commitment to implementing the online harms white paper and vowed to create a regulator that would impose sanctions on tech companies failing to abide by a code of practice.

These sanctions would include fines, he said, but also place responsibility on company directors and potentially lead to sites being blocked.

“We expect, we deserve and we will require that some of the cleverest companies in the world use their ingenuity to protect us, as well as to sell to us,” he said.

He added that guidelines for websites and apps on how to safeguard children from inappropriate content would be published in the autumn.

Jim Gamble, a former chief executive of the National Crime Agency’s child exploitation and online protection division, said the government had been too quick to blame tech companies.

He said child vulnerability and mental health issues were the root causes that needed to be tackled, and these problems had been exacerbated by Conservative austerity measures.

“It’s easy to point the finger of blame and I think we do it too frequently at industry, perhaps not frequently enough at parents, but definitely we do not point the finger of blame where it belongs at government often enough,” Gamble said.

He also criticised the Tory leadership favourite Boris Johnson for saying money spent on investigating historical child sexual abuse allegations was “spaffed up a wall”.

Gamble added: “To use a word with a sexual connotation like that is appalling, and I want to say to him that it’s time that he came out and gave the full explanation of himself, and delivered an apology to every survivor who has felt hurt by that.”