Watch 49 Up tomorrow

ITV are showing the latest installment in Michael Apted's documentary series at 9 p.m., with a second episode on September 22.

Apted has followed a group of children since they were seven. The first documentaries were shown in 1964, and has gone back to them every seven years ever since. They are among the most important documentaries ever shown in Britain. I remember our class spending an entire double English lesson talking about 21 Up in 1977 or 1978 because it was all we (and the teacher) could talk about.

Jonathan Freedland writes about the series in today Guardian:

Granada's intention in 1964 was to make a polemic about class, to show that the course of Britons' lives was determined by their backgrounds. So it showed posh boys at prep school who, aged seven, could confidently name the Oxbridge college they planned to attend - and working-class girls discussing what they would do if they had a lot of money, "like two pounds".

But Britain was to surprise the film-makers. They had divided the nation into toffs and cockney sparrows - and all but forgotten the middle class in between. And yet central to the story of British life over the next four decades would be the huge expansion of the middle class.

And:

Social shifts are visible too. When Simon was born, he recalled at age 21, an "illegitimate child was something whispered about". Now, among this group, there are countless children and grandchildren born outside marriage and no one seems to notice.