It may involve the occasional seeping of blood from a pupil's mouth, but here's my suggestion for a sensational lesson for primary and secondary teachers: cheek-scraping. The family history website Ancestry.co.uk is now offering to collect DNA samples, passing on "matches" to those who participate. So your class could potentially learn of blood relatives across the world, or, indeed, across the village.
I doubt if fresh-faced schoolchildren are the main target market for the spatula (particularly since the DNA test kit costs pound;74 per person), yet this is a project that British teachers and Ancestry.co.uk should seriously think about working on together. It would surely be in the website's interests to offer an affordable school discount, given the rich and appetising volume of DNA data that British schoolchildren could supply to this new bank.
It is also much better if ancestor research happens in youth, rather than adulthood. Children will set about it without baggage. They have not spent decades nurturing false dreams and prejudices about who they are and where they come from. It is a far more disorientating business if the genealogical mission is left until later on in life - and not as helpful.
A case in point was the latest BBC series of Who Do You Think You Are? which bore witness to much deluded barking up erroneous ancestral trees. John Hurt set off dreamily to his presumed Irish homeland, found no relatives there at all and ended up in Grimsby. Graham Norton rummaged around Ireland too, but wound up in Sheffield. Alistair McGowan began the programme as part-Portuguese, part-Scottish; an hour later, he was Indian and part-Irish. Nothing wrong with any of these outcomes, of course, but they all caused a major shock nonetheless. Years of wasteful misconception.
There have been similar and perhaps even more bloodline-busting discoveries in America recently. The Republican Vice-President Dick Cheney has learnt that he is a distant cousin of the black liberal senator, Barack Obama. Difficult to say which side was more shaken by this news. "Always knew there was a black sheep in the family" was the reported response from the Obama camp.
Meanwhile, US singer Mariah Carey was hoping to confirm that the "Cole" among her antecedents meant that she shared the same genes as the arguably more talented Nat King Cole. She discovered instead that her pedigree is shared with the Chelsea defender Ashley Cole. As Mariah might now sing if she were to perform Cole (no relation) Porter's hit I Get a Kick Out of You, "Mere Ashley Cole doesn't thrill me at all".
Enough of such adult folly. Let youngsters find out about their personal roots and connections at the earliest age possible, before their elders mess their heads up too much with notions of class, "pedigree", "skeletons in cupboards", "black sheep", and the like. The more our youngsters discover that their relatives include people from a colourful mix of social, national, religious and ethnic backgrounds, the more we can help to make a nonsense of prejudice in all those areas. That's got to be worth a few cheek cells.
Stephen Petty, Head of humanities at Lord Williams's School in Thame, Oxfordshire.