James is 15 years old, coming up to his GCSEs; and the researcher he is talking to is clueless about girls. Yes, he tells her, girls at his school, underage girls, do indeed have sex. With guys in their class, like him. The researcher is surprised. Haven’t girls gone studious; aren’t they collecting the top grades, leaving the boys behind?
James states the obvious. ‘It’s not girls with As or A*s,’ he explains. ‘Girls with As are virgins.’
Today, almost a quarter of girls report having underage sex. But there are almost as many girls waiting till they’re 20 or more. This isn’t random, a question of whether and when the right boy appears. Instead, it’s a parting of the ways. One group of girls is setting off along an alpha track, leaving their contemporaries behind; and teenage sex lives are a very good predictor of who they are.