With an actuary and a computer software engineer for parents, seven-year-old Oscar Selby was destined to be mathematical.
But his love of numbers and ability to learn quickly marked him out and today he scored an A* in his maths GCSE at less than half the age most youngsters take the exam.
Oscar, from Epsom, Surrey, is believed to be the youngest to score the top grade in a GCSE exam.
He spent four hours every Saturday for nine months studying for the course through Hertfordshire-based Ryde Teaching.
He said: "It was hard work but I did enjoy it.
"I was rather nervous on the day of the exam but it was easier than the normal ones I had done.
"I answered every single question."
Oscar, who attends Stamford Green Primary School in Epsom, said he hoped to concentrate on science next although he may go back for further maths studies later.
As well as enjoying numbers, he takes a keen interest in chemistry, is an avid reader and also enjoys computer games, chess and football.
Oscar lives with his parents Natasha Regan and Matthew Selby and five-year-old twin sisters Margot and Constance.
His mother, a 39-year-old part-time actuary, said: "He has always been very interested in things and very bright.
"He has always liked big numbers - if you talked to him about 1,340,000, for example, he would get very excited."
When Oscar was in reception, teachers discussed his maths abilities with her and she praised his school for trying to challenge him.
But after doing extra work with him at home, the family decided to enrol him on the GCSE course.
"I think it's good for him because he is quick to pick things up," she said. "If he can do it I think why not? It means he can get interested in other things as well so it's not just about maths.
"He is having a normal life as well. During the course he did all the normal stuff during the day and after the girls had gone to bed we would do a bit of maths.
"It involved four hours on a Saturday in Hertfordshire so that's quite a chunk of time but he was up for it.
"The thing about him we noticed really early is how focused he is. He has very good concentration and gets very engrossed when he gets into something - it's nice to encourage it."
She said the family spent the day of the exam together, going out for a meal and letting Oscar chose some new books.
"I think he is young enough that it didn't really faze him at all," she added. "We went along and it was like a day out."
Ms Regan, who said the family plan to enrol on a cookery course together next, said Oscar raised £3,500 in sponsorship for taking the GCSE.
It will go to the Cystic Fibrosis Trust because a girl in his class has the disease.Reuse content