How big is a barrel? Wikipedia says that an oil barrel contains 42 US gallons or 34.972 imperial gallons, but I find it hard to visualise such measurements. Burn Up (BBC2) was a drama in which businessmen spoke about barrels of oil as if they knew what they were talking about. Like most businessmen in dramas, they talked very quickly, alluding to things we ordinary mortals know nothing about. Yet these oilmen seemed unaware of controversies about global warming until the subject was explained to them in supposedly elementary terms. Even this explanation included such unhelpful statistics as the prediction of a 78cm. rise in sea levels by the end of the century (how high is 78 centimetres?). Oh, and methane gas is 23 times more devastating than carbon dioxide (so what's all the fuss about CO2?).

These incomprehensible statistics were matched by the puzzling nature of the drama, in which Tom (Rupert Penry-Jones, pictured) chairman of an oil company, gradually becomes converted to environmentalism. Tom goes to the Arctic to see global warming for himself (in less than a day, just like David Cameron). As the story progressed, it became more and more unlikely and impenetrable, especially as half the dialogue was obscured by loud background music and noise. By the end of the first episode, I was as mystified as I was incredulous. The concluding part is on tonight but I wouldn't bother.

In John Barrowman: The Making of Me (BBC1), singer and actor Barrowman was as hot for certainties as those environmentalists who are sure we are all doomed. Like many people on TV these days, John was going on "a journey into the unknown". The commentary explained: "John is gay and he wants to know why," but it was obvious that John really sought proof that his homosexuality was inborn rather than learnt - nature, not nurture.

Like many of the scientists he visited, he seemed to think it was an either/or situation, but surely many people go through 'gay' phases or are bisexual? In the US, John met a man who was gay until he decided it conflicted with his religion and he decided to 'go straight'. Yet John underwent numerous tests to prove that he is naturally gay, even though one researcher found that John's index finger was shorter than his ring finger - apparently a sure sign that you are 'straight'.

I am certain of at least one thing: that some people have more money than is healthy. Personal Services Required (Channel 4) has been a brief but eye-opening series. In each episode, two rich families have tested three separate applicants for jobs in their households. Some of the job applicants have their faults but invariably the host families have been appalling: treating their servants patronisingly and expecting them to work like slaves. In the last episode, applicants were tried out by a marketing man with two abominable teenage daughters (both spoilt brats) and Lady Swinton, whose staff have been leaving in droves. One perhaps surprising outcome of the series is that the male job-seekers were generally more employable than the females.

The government spends billions of our taxes on education, yet numerous people leave school without basic literacy skills. This suggests there is something wrong with our education system, which can't even teach people two of 'The Three Rs'. Can't Read, Can't Write (Channel 4) got Phil Beadle, "Britain's best-known teacher" (never heard of him!), to try teaching some adults to read and write. The arrogant Phil didn't seem ideal for the job, because he used difficult words like 'kinaesthetic' and had never taught grown-ups before (or taught anyone to read). He seemed fixated with phonics but this approach clearly didn't work with all his nine pupils, who he tried to teach in a class even though some of them were uncomfortable being taught with other people. Isn't it evident that you can't teach everyone in groups? People need individual attention and methods tailored to their personal requirements.