Brad Pitt, Hillary Clinton, Oprah Winfrey and J.K. Rowling - not perhaps natural bedfellows, but linked by a common thread nonetheless. Along with more than half of all US presidents - including George W. Bush - 21 of the first 23 men in space and 40 per cent of company chief executives, they are all the first-born child in their family.

The widespread view is that first-borns are confident natural leaders, who love to be in charge and relish responsibility. At the other end are the last-borns, the rebels who are used to bending the rules and crave the limelight. Squeezed in between are the creative and adaptable middle children, able to see both sides and good at brokering compromise.

Is there any truth in these beliefs? And does birth order make a difference to how teachers work with pupils in their class?

Much effort has been put into trying to prove the stereotypes right or wrong. And while there is a wealth of evidence on either side, there is still no consensus. However, there is agreement that birth order effects are most likely to be felt within the family.

In school, any impact will be most obvious at reception age. First-borns are the first to leave the home environment, and this can make it harder for them to settle into school at the beginning of the year, according to Rebecca Sowden, a reception teacher at a school in Newcastle. “I have found the children who suffer separation anxiety tend to be only children or first-borns,” she says.

Naturally there are exceptions. First-borns who have close relationships with cousins or with older children can be well-prepared for school, but she does recognise some shared characteristics. This also applies to second and third-born children.

“Children who have seen older siblings go to school and survive are more self-assured in the initial stages,” she says. “They tend to be better prepared for what they are about to face and often relish the opportunity to do as their big brother or sister does. Some come to school saying, “I want to read” or “When can I do some homework?”

But if first-borns find it difficult to settle initially, this soon fades and they often go on to be high-achievers, says Mrs Sowden. In her experience, the attainment of these children is often high. One possible reason is that parents of first-borns, and perhaps particularly of only children, have more time available to support their child.

“Although there can be some separation anxiety at the beginning, these children tend to settle well and can enjoy high levels of self-esteem, strong vocabulary and well-developed communication skills,” she says.

This chimes with the theories of Kevin Leman, a US psychologist and a leading proponent of birth order as a factor in shaping personality. He believes that as the guinea pigs of the family, first-borns are held to a higher standard than their siblings, and more is expected of them as children.

This follows in the traditions of the study of birth order. It began in 1874, when Sir Francis Galton, chronicling the lives of eminent scientists, observed that 48 per cent of them were either first-born or only sons (women were not taken into consideration, so a scientist counted as a first-born even if he had older sisters).

Successive studies have sought to prove, with varying degrees of success, that birth order is important. One of the most influential in recent years has been into IQ tests taken by 240,000 conscripts into the Norwegian army, which found that first-borns scored 2.3 points higher than second- borns. Although this may not seem much of a difference, it is statistically significant.

This seems to be in line with parental expectations. A survey by parenting website Netmums.com this year found that 35 per cent of mothers thought their first child would be the most academically successful, compared with only 6 per cent for their middle child and 15 per cent for the youngest.

This invites the possibility that it is the expectations fuelling the achievement, rather than the other way around. If these expectations feed into more attention and pressure to perform, then eldest siblings may well end up achieving more. This seems to be the experience of Kate Aspin, who believes it is parental expectations rather than birth order that is most influential.

“Sibling order only becomes an issue if the family has a particular take on a child,” she says. Children whose older siblings are successful at school may struggle to fulfil their parents’ expectations, she says. In some cases, this leads to parents wanting to label their children as having special needs rather than accept that they are of average ability.

Mrs Aspin, a former primary deputy head and now senior lecturer in education at Huddersfield University, recalls a set of twin boys who fought constantly - one eventually broke the other’s nose - where birth order was frequently raised in their arguments. Similarly, she recalls an only child where the weight of expectation was such that his failure to get into grammar school was seen as a catastrophe. But often it was parental expectation that was the crucial factor, she says.

The advantages of being the eldest do not just stop at IQ. Later-born siblings tend to be shorter as well. For boys, the odds on being gay increase for each older brother, although this effect is not replicated for girls with older sisters. First-borns account for 52 per cent of US presidents and 43 per cent of company chief executives. But UK prime ministers do not fit this pattern. Only five of the 20 prime ministers of the 20th century were first-born, including two only children. Intriguingly, the choice at the next election for proponents of the birth- order effect argument look likely to be between a middle child (Gordon Brown), a youngest son (David Cameron) and the third of four (Nick Clegg).

While first-borns may face more pressure, younger children tend to receive more affection. Studies of parents with two children found that at least half admit to loving one better than the other, and for more than 80 per cent this is the younger one.

Birth order has its detractors among the academic community, however. Prominent among these is Judith Rich Harris, a US psychologist, who argues that “birth order affects the way children behave with their siblings and parents” but has little or no impact on personality outside the family.

She cites studies showing that when it comes to interacting with peers, first-borns are not more likely to dominate and latter borns are not more easily led. That these roles are often adopted within families has a simple explanation: age. First-borns will always be older than their siblings and so are more likely to lead and take responsibility, while differences in education and socioeconomic status account for differences in achievement and IQ between first and later-borns, she argues.

But the importance of family relationships helps to explain why a belief in the effect of birth order is so enduring. While she observes some differences among her pupils, Mrs Sowden says when adults talk about their experience of childhood, birth order is often seen as fundamental.

“One of my friends talked about always being compared with her older sister by teachers at school,” she says. “She felt that she hadn’t achieved her potential and has since been driven to do so by completing a degree at the same time as having a new baby.”

The experience of Liana Peck, a food technology teacher in Barnsley, suggests birth order is not a consistent factor among her pupils. While a hard-working older brother and attention-seeking younger sister fit the stereotype, in sisters in Years 10 and 7 the roles are reversed: it is the younger one who is well-behaved and the older one who lacks motivation. Two other sisters, this time in Years 11 and 8, share similar character traits and are both disruptive.

Children from multiple births also skew the theory slightly. Twins in Year 11 are both hard-working and predicted As at GCSE, but two out of a set of triplets differ widely, with one predicted a B and the other a D, she adds.

Where birth order is most apparent is among only children, argues Chris Wheeler, RE teacher at Ashton on Mersey School in Cheshire. “They are really easy to spot: the world revolves around them,” he says.

“They tend to ask a lot of questions and they are never wrong, which probably goes back to getting all the attention when they were growing up,” he says. They are also often eager to please and first to volunteer to help with jobs around the classroom.

But it is much harder to place other pupils in their birth order on the basis of their behaviour or achievement, he says.

He recalls a family he taught in Birmingham: the three older boys had a school-wide reputation for poor behaviour while their younger sister was the opposite.

“She was an angel and she was so placid,” he says. “If you asked someone to hand out the books she would have her hand up straight away.” Like Mrs Aspin, he sees family situation as a more significant factor than birth order.

“Some children will fit the mould, but there are just as many where it is completely the reverse and the oldest ones are complete rebels and the younger ones engage well,” he says.

Perhaps birth order is a bit like astrology: you can pick what you like out of it and something is bound to apply. You can use it to guide the way you work, but if you ignore it you may do just as well.

Fist among equals?

Addressing parental expectations is a perennial problem for teachers, particularly for first-borns. But the advantage teachers have is that schools provide a respite from the home context where these attitudes are cultivated.

The school environment provides an opportunity for the child to be treated as an individual rather than a first-born, explains Kairen Cullen, educational psychologist and former teacher.

“School offers an experience that is less emotionally intense and less charged with parents’ expectations,” she says.

Parents of first-borns may need extra reassurance that their child is getting the support they need, both academically and socially. Listen to their concerns and aspirations and then put forward what is possible, suggests Mrs Cullen.

“You are not only educating a child, you are educating a parent, particularly for the first-born.”