Of course I thought I was going to be watching porn starring mums. It’s the punchline that’s been adorning student T-shirts for decades: Support Single Mothers … Watch Porn! Arf arf.

Only, in this case, we’re not doing that. Instead, we’re following a group of five disparate women try to make a porn film they’d be happy to exist out in the real world. The fact they are mothers is not necessarily surprising – a lot of people are – but it does add poignancy to their feelings about the effect pornography has on young people. When Sarah, a single mother of a young teenage daughter, starts shaking after seeing a link to a film titled, simply, ‘girl gets raped,’ it’s hard not to share her concern.

Ever since the proliferation of free, online pornography (most of which is accessible without age verification) the sex industry has changed. In his podcasts The Butterfly Effect and The Last Days of August, writer Jon Ronson has taken a long and careful look behind the screen into the industry, economics and after effects of pornography’s new incarnation. But the women in new Channel 4 documentary Mums Make Porn aren’t necessarily doing a deep dive into a moral microcosm; their remit is more active, more specific and, in its own way, rather more sweet. They are going to turn their hands to making their own porn film – one they might feel more comfortable with their own children watching, and that they would actually find sexy to watch themselves.

In classic Big Brother style, the producers have brought together an eclectic group: Emma the west London pop stylist who’ll be acting as set dresser; Sarah the photographer and single parent from Chester who will be the director; Jane the devout Christian who encouraged her daughter to join a feminist protest outside the Playboy club; Anita the mother of four boys who happily admits to enjoying porn already; and Sarah-Louise, a Mancunian beautician who will be doing hair and makeup on set and who, along with Jane, has never before watched live sex. The seeds are sown for drama and discord down the road, of course, but in the initial stages all five women come across as thoughtful, open-minded, reasonable and caring. They’ve volunteered for the project not just to get on television (although they are, of course, on national television) but because they have a direct investment in the future: their own children.

Facebook Twitter Pinterest ‘Shoutout to Gary Lineker!’ ... Emma, Anita, Sarah-Louise and Sarah (l-r) in Mums Make Porn. Photograph: Dave King/Channel 4

In the opening episode, the women come together in front of a table of scones and freshly cut flowers to watch an assortment of pornography on Emma’s laptop. This hardcore content is the very sort of thing any young person with access to wifi can find, for free, with just two clicks. It may be illegal to watch it under the age of 18, but for anyone older, it is entirely legal. Cue the banter: ‘She’s got four penises in her, or is it three? I’ve lost count.’ After their initial introduction to the world of porn, all five women draw up a list of key terms for their project (romance, consensual, foreplay) which eventually turn into moodboards, one of which gives a special shoutout to Gary Lineker. ‘Can we solve it with one video?’ asks Sarah, before immediately answering herself: ‘I’m not sure’.

Next come two field trips to porn sets. In the first, we learn that Gaviscon can be an excellent semen substitute, and watch Emma congratulate the two performers for being ‘brilliant’ while handing them a piece of kitchen towel freshly torn from the roll. At the second, Sarah-Louise actually gags over a garden fence and the male performer loses his erection (according to Ronson, one of the many side effects of the proliferation of free pornography is a huge simultaneous increase in erectile dysfunction among young men. But that, as they say, is another story.)

For me, the most interesting moments are the vox pops featuring real life teenagers that intersected the main documentary. To hear young men explain that porn is where you learn what to do in the bedroom is depressing but not surprising, even when it comes directly after a scene in which a professional porn performer explains that pornography is fantasy, make believe, and not a model for real sexual relationships.

Can these women make a successful porn film? By the end of the opener, it would appear unlikely. But can they make an important point about how access to hardcore pornography among children as young as 11 can effect their emotional and sexual development? Certainly.

Mums Make Porn starts tonight on Channel 4 at 10pm.