Gordon Brown showed off his strong serve as he smashed a double ace over the net in an echo of predecessor Tony Blair's own photoshoot on the tennis court.

Mr Brown scattered the opposition as he drove the ball over the net at the West London Academy, in Northolt, a school which specialises in sport.

The Prime Minister took time out from playing tennis yesterday to put competitive sport in schools at the centre of a new campaign in the run-up to the London 2012 Olympics. The £100m campaign aims to offer an hour of sport to every child, every day of the school week, and includes plans for greater emphasis on competition within and between schools.

It will also include a new National School Sport Week, championed by former track star Dame Kelly Holmes, where all schools will be encouraged to run sports days and inter-school tournaments.

A network of 225 competitive sport leaders will be set up to work with primary and secondary schools to increase the amount of competitive sport they offer.

The Prime Minister said: "We need to put school sport back where it belongs, playing a central role in the school day. I was lucky enough to have primary and secondary schools that had sport at the centre of their ethos. I want every child to have that opportunity to take part."

Mr Brown announced the campaign yesterday at his visit to the London school with culture secretary James Purnell, who said: "Competitive sport is enjoyable and good for all children and young people, not just those who excel.

"It helps improve children's teamwork and social skills, and boosts confidence and self esteem."

His minister for schools and families, Ed Balls, joined Mr Purnell and Mr Brown in playing tennis, but took a more gentle approach and enjoyed a leisurely knockabout with some of the pupils.

Unlike Mr Brown, his predecessor, Tony Blair, preferred to be pictured when playing sport with a well-known figure. In 2002, he played a reportedly well-contested tennis match with Wimbledon star Pat Cash at the Queen's Tennis Club as part of Sport Relief.

Meanwhile, Dame Kelly demonstrated trampolining skills as she performed a complicated series of flips in front of the school team.

As she dismounted, she invited Mr Brown to have a go, and said jokingly: "It's your turn now." He chuckled but politely declined.

Dame Kelly and Mr Brown also spotted a talent of the future in the form of 11-year-old Igor Morais as he darted around a table tennis board. Dame Kelly presented him to the assembled visitors, saying: "This is a future talent. This is what school sports are all about - getting the opportunity to see a star."

She asked the 11-year-old: "Do you like your table tennis, do you want to go to the Olympics?" He nodded enthusiastically.

The group later visited the nursery section of the academy, which holds three schools teaching children, ranging in age from three to 18. Mr Brown sat down with a group of slightly overwhelmed four-year-olds for story time. The children were being told a story about zoo animals and each carried a model of a different species.

He chatted with them about the different noises made by the animals they were holding and joined in with the actions as they showed him what a crocodile does with its jaws. He later spotted a book, Dear Zoo by Rod Campbell, which he said was a favourite of his son. Earlier he delighted older children as he elicited their football allegiances.

He told Dame Kelly he had found a few Arsenal supporters and responded by giving them high fives. The school, which has 1350 pupils, already teaches two hours of sport a week with the extra three hours, as planned by Mr Brown for schools throughout the country, clocked up in after-school clubs.

Specialising in sport and enterprise, it offers a diverse range of activities, from football and basketball to climbing, dance and even disabled curling.

Table tennis is coached by Commonwealth champion and Ireland number one Jason Sugrue, and a football academy is also based there.