Last Night's TV: Seven Days/Channel 4<br />Britain's Youngest Boarders/BBC2<br />Michael Wood's Story of England/BBC4

I hope no one sees me in here," said Sam, diving into a Soho sex shop in a hunt for a French maid's outfit. Channel 4, on the other hand, will be very much hoping that millions of people see Sam in the sex shop, and Channel 4 is far more likely to have its hopes fulfilled, since the sequence was part of their heavily promoted new reality series, Seven Days, which follows the lives of various Notting Hill residents over the course of a week, hastily guts the footage for the best bits and then puts it on screen to stimulate our gossip receptors. "Their lives are unfolding now," reads the title card at the beginning of the programme. "Tell them what you think they should do next." Given Sam's ingenuous remark it's possible that she hasn't yet fully grasped the implications of the contract she signed, but, unless they're doing a lot of heavy-obscenity filtering on the website, which allows viewers to prod the participants, I imagine it's beginning to dawn on her by now.

The wisdom of the crowd – an unreliable resource at the best of times – is being tested in two ways here. Channel 4 has hinted that the programme itself will adapt to the immediate response of the audience, so that much-loved characters (they have a status somewhere between real people and dramatis personae) will come to the fore, while less favoured ones will drop away, perhaps to be replaced entirely. At the same time, there's an implication that viewers will provide an unpaid consultancy service for those hovering on the brink of big decisions. Should Hannah, the oh-yah trustafarian who's about to take over mummy's interior decoration business, hook up again with ex-boyfriend Dougal? And is Moktar, the Muslim law student, wasting his time incurring all that student debt, even if he does think of himself as treading in the footsteps of Malcolm X and Gandhi? Will any of them actually be stupid enough to let a narrative-hungry television audience influence their behaviour?

Given something with this many variables, I think Chaos Theory is the only reliable predictive model. How far will some participants go to keep themselves in the limelight? And how toxic might public attention get, given that the guinea pigs aren't hermetically sealed in a human vivarium, as was the case with Big Brother, but are walking the streets going about their business? The first episode suggested that even a relatively low-key week should provide enough narrative juice to keep the engine ticking over, but what kind of horrendous feedback loop might occur if the tabloids get interested and day-to-day life gets bent out of shape completely? The image that comes to mind is a magnifying glass on a sunny day, and a wisp of smoke beginning to rise from an ant's abdomen.

This week's episode was mostly pump priming, establishing the Dickensian range of an urban cast list that runs from a black would-be rapper (who gets a stern talking-to from his formidable aunt when he hints that he might be considering signing on) to well-to-do types with hobby-jobs. Sam and her equally leggy new flatmate, Laura, hogged most of the airtime, since their appearance as dominatrix French maids at a London Fashion Week event offered the most in the way of bickering comedy and visual attraction. But there are others who look as if they may provide some rivalry for centre stage, including a laboriously flavourful character called Malcolm and a hairdresser called John, who, like all the others, seemed unusually fond of reading out bits of the newspaper, so as to underline the just-harvested nature of the footage. "What do you think the public are going to think about me?" asked Sam's friend Laura towards the end. I haven't a clue, Laura, but I'm almost as curious as you are to find out.

Britain's Youngest Boarders was a more conventional slice of contemporary life, a documentary following some of the new boys at Sunningdale School, a top-drawer prep school that feeds into the most prestigious public schools in Britain. It was also a study of inherited privilege and the acquisition of the easy, uncomplicated confidence that one's place in the world is somewhere at the top. "I was really sad actually," said one older contributor, recalling his own arrival at the school, "because I was quite immature at the time and I thought, 'God, why have my parents dumped me in this place?' But I grew to... like it almost as much as home really." Quentin, who offered this sage perspective, is now 11. Extra-curricular activities included clay-pigeon shooting, Eton Fives and golf, and the tuition extended to handshake lessons, it never being too early to learn that you can grip the world firmly and stare it straight in the eyes. Not officially on the curriculum, but being absorbed well all the same, were lessons in the suppression of strong emotion and the maintenance of a stiff upper lip.

Michael Wood's Story of England examines the national narrative through a deliberately narrow aperture, focusing on a single Leicestershire village called Kibworth. In a thousand years' time historians will presumably be able to watch Seven Days if they want to know what life was like for 21st-century town-dwellers. Here, for the moment at least, bits of pottery, place names and the odd fragment of chronicle are all they've got, but it's surprising how far those will go. I'm not sure I can always match Michael Wood for wide-eyed wonder, but it's fascinating television even so.