When children start school is not important
Should we let children stay children for as long as possible, or is an early school start important to prepare children for life in a knowledge-based society?
Parents have their children's future prospects in mind when they send them to school, and how children's prospects are affected by how old they are when they start school is precisely what Professor Kjell G Salvanes at the Norwegian School of Economics (NHH) is researching.
'How old children are when they start school has no effect on how they get on later in life,' claims Professor Salvanes.
An early start in Norway
His claim might calm nervous parents, but it conflicts with the generally accepted view.
'Our results contradict the normal perception in the literature and society at large, namely that the age when children start school actually matters,' says Professor Salvanes.
He finds no effect of children's age when starting school on future earnings or cognitive capacity. It has been a commonly held belief that the older the child is when starting school, the better it will learn, because it means that the child is both older in years and more mature than his/her classmates.
Because of this belief, which there is some support for in empirical research, between ten and twenty per cent of boys in the USA have been held back a year before starting school. In Norway, the opposite attitude prevails: Statistics show a slight tendency for people to let their children start school a year early.
'Our findings show that parents can stop speculating when it is best to send their children to school. Nor is there any point in planning births for specific months in order to influence school-starting age,' says the professor.
Military experiment
Together with Sandra E Back and PaulDevereux, Professor Salvanes has used data from the Norwegian Armed Forces to see how people who started school at different ages perform on IQ tests. They also studied earnings development for individuals between the ages of 24 and 35.
'In school, the age within one school grade can vary by almost a whole year. Children born in January are in the same class as children born in December. This means that it is possible to distinguish between age and school-starting age. We used the results of IQ tests taken as part of military service examinations when the students are about 18 years old. This allows us to compare children who are the same age, but who started school at different ages.'
The Armed Forces' testing of young people thus functions as an unintended natural experiment, which the researchers have made use of. The results are striking. How old you are when you start school has little or no effect on the test results, although, as expected, actual age had a favourable effect.
'Previous studies, which found that starting school early had a favourable effect, used pupils' marks upon finishing compulsory schooling as a criterion, and were therefore unable to differentiate between age and maturity when the test was taken and age on starting school. By testing later, you avoid this trap,' emphasises Salvanes.
Effect on earnings
The study is the first of its kind to study how school-starting age affects earnings.
'Earnings is an important outcome that can say a lot about how people manage after finishing school. We observe that starting school late has no long-term effects on earnings, although those who start school late are slightly behind until they turn 30. This also seems natural, since those who start late are also older when they start working,' explains the NHH professor.
Other studies conducted by the researchers show that earnings at the age of 30 is a very good indicator of lifetime earnings.
Individual considerations important
'Our results show that there are no general advantages of holding children back or letting them start school early. This does not mean choosing one or the other would not be beneficial for some individuals, but there is no general gain,' Professor Salvanes says.
This work is part of a larger project in which the researchers are studying factors relating to how long one should stay home with a child after birth, when children should start kindergarten and, finally, when they should start school.