If you want advance warning of what's in store from your pupils at the start of each school year, try asking them their place in the family, also known as birth order.
First-borns are more likely to be self-assured, assertive, competitive and dominant compared with last-borns. First-borns are exceptionally common among leaders, such as prime ministers and presidents. They are more liable to be conscientious, to endorse conventional morality, to be identified with their parents' values and obedient to parental authority. Keep an eye out for these potential teachers' pets.
They also achieve more in their careers, having done better at school, with parents pitching conversation at their level rather than that of younger siblings. They are more anxious about their status, more emotionally intense and less quick to recover from upsets. They are more vengeful and prone to anger. They tend not to enjoy risk-taking in general, and dangerous sports in particular. They do not savour backpacking and world travel.
Last-borns are generally different in all respects. They are less self-confident, more altruistic and emotionally empathic; when small, they get more involved with other children. They are less conscientious and less prone to anger and revenge, more sociable and easy to be with. They are far more open to experience, being unconventional, adventurous and rebellious. They embrace risk taking and contact sports, and are more likely than first-borns to prefer such pursuits as rugby and football.
A major reason for these differences is that, depending on your birth order, you adopt different strategies to get your parents' attention. Given that there can never be enough love to go round, you have to carve out a niche for yourself to attract it, cultivating different skills and personality attributes from your siblings.
The eldest tends to take the line of least resistance, embracing the attitudes and behaviour of its parents. By the time the youngest comes along, depending on the size of the family, there may be no parent-aping niches left to occupy. To mark themselves out they must be more unconventional in terms of parental values.
Middle-borns are less predictable. If the oldest child has left some parent-attracting niches vacant, the middle-born may be quite conventional. But if they are the third or subsequent child, but not the youngest, there may be fewer niches left and they may be more like a last-born. And only children? They are similar to first-borns, but more secure - after all, there are no vile siblings to steal the attention.
Frank Sulloway, an American psychologist, shows how significant birth order is in fashioning the interests of politicians and scientists. Whereas the professional revolutionaries from history, such as Leon Trotsky, are liable to be later-borns, establishment politicians tend to be first-borns.
Scientists who are later-born, such as Charles Darwin, are more likely to develop radical theories than first-borns. The later born a scientist, the greater the diversity of their interests, perhaps because being multi-talented increases the chances of striking a parental chord.
The size of the gap between you and your nearest sibling affects how much impact birth order has. Among famous historical figures, the greater the gap between siblings, the less likelihood that a younger sibling would be politically revolutionary or scientifically radical because there is less need for the later-born to reject the status quo in order to get parental attention.
Small gaps are potentially harmful because parents are harder pressed to meet their children's needs when tiny and demanding. In one study, adults who have a sibling less than two years younger are more at risk of schizophrenia than those with larger age gaps.
Another study finds that children who have been exceptionally gifted before developing schizophrenia are significantly more likely to be first-born than normal gifted children.
All of which should make you add birth order to the long list of other psychosocial indicators of what is making your pupils tick.
Oliver James is a child clinical psychologist and author of The Selfish Capitalist and Affluenza
James, O.W. They F*** You Up (Bloomsbury, 2007) 44-52
Sulloway, F.J. Born to Rebel (Abacus, 1996)
McKenzie, C.D., et al (1996) Delayed Posttraumatic Stress Disorders from Infancy: The two trauma mechanism Harwood Academic Publishers
Isohanni, I.I, Jarvelin M.R. (1999) Can Excellent School Performance be a Precursor of Schizophrenia? Acta Psychiatrica Scandinavica 100:1, 17-26.