-Kate tried her hand at table tennis while Harry joined the basketball court and William took to the football pitch
-Prince Charles and Camilla in Tottenham to witness Olympic torch relay before it arrives at Buckingham Palace where it will be greeted by young Royals
By Rebecca English, Royal Correspondent
Princess of ping pong: The Duchess of Cambridge plays table tennis as she visits Bacon's College to launch the Coach Core programme today
With just a day to go before the opening of the London Olympics, the Duke and Duchess of Cambridge and Prince Harry were entering into the spirit of the Games today. Kate and the two princes were attending the launch of a new sports project in south east London that aims to train the next generation of sports coaches.
Young trainers were putting some 100 students through their paces for the royal trio, whose charitable foundation is supporting the initiative. Judo, basketball, five-a-side football and table tennis will be demonstrated for William, Kate and Harry during their visit to Bacon's College in Rotherhithe.
The three young royals were also due to try their hand at some of the sports on offer - although perhaps, a Palace spokesman laughingly said, not the judo.
Prince Harry was due to take part in the basketball, William football and Kate table tennis - as well as watching the martial arts. On the football pitch William sweated in the heat as he kicked a ball, dribbled it through some cones and then wildly mis-timed a shot at goal.
Prince Harry missed his four shots at goal in the basketball but Kate looked quite a dab hand at table tennis. Kate looked the picture of summer perfect in a patterned white and beige Hobbs summer dress, low beige wedges and with her trademark blowdry.
Kate's 'Wessex' dress cost £35 in the sale from High Street store Hobbs but is sold out.
Hidden talents: Onlookers said Kate was a 'dab hand' at the sport as she ably took on an opponent from the club
Known for her sporting prowess, Kate recently impressed members of the British hockey team too when she took to the pitch to show off her dribbling skills
The Duke was joined by Michael de Giorgio, chief executive of Greenhouse, and chatted to some of the coaches who were taking the lessons.
But William could not resist joining in and lined up with a group of youngsters for shooting practice. The royal shimmied through some cones then passed the ball to a trainer who returned it for the shot, but William hit it just wide of an empty goal.
With his head bowed he trudged back to the middle of the pitch but a few minutes later had the chance to redeem himself when the students were asked to volley the ball into the net.
As William ran forward the trainer threw the ball into the air and shouted 'keep your eyes on it' but the royal sent it just over the bar but received the encouraging comment 'much better' from the coach.
In a short speech about Coach Core William jokingly likened himself to being a 'giraffe on ice skates' on the football pitch and ribbed his brother Harry about 'cheating' to become the fastest man on earth - a reference to his legendary race against Usain Bolt in Jamaica earlier this year'.
But he charmingly described his wife, Catherine, as being ' a sight to behold with a tennis or hockey stick in her hand'.
The Coach Core programme is being piloted by the organisation Greenhouse and will train 16 to 19-year-olds to become qualified coaches and mentors for their schools and communities.
The hope is that the talented young sportsmen and women will be able to inspire their students and build a future for themselves in sport.
Forget your kit, Kate? She may not have the right attire, but a very game Duchess of Cambridge attempts to dribble a football wearing her Pied-a-Terre wedged espadrilles
If it proves successful, the foundation aims to roll out the initiative to other sectors where inspirational young coaches can become role models for and inspire young people.
'The Royal Foundation of The Duke and Duchess of Cambridge and Prince Harry wanted to develop a sports programme in recognition of London hosting the Olympic Games and developed the Coach Core concept with Greenhouse charity,' a spokesman for the three said.
William made a speech and thanked John Martin, the Headteacher, the staff and pupils of Bacon's College for hosting the event and giving himself, Kate and Harry such a warm welcome.
'Over the next month, the eyes of the world will be on Great Britain. For us to hold the Olympic and the Paralympic Games here in London is a great moment for our Nation, which itself is steeped in sporting history.
'Therefore, for Catherine, Harry and me there could be no better way of starting this epic time than being with you here in Rotherhithe, so close to the heart of London 2012, to launch Coach Core,' he said.
The young Royal told of how important coaching is within the sports field.
He said: 'Coaching is a vital part of any sport. Being properly coached, really knowing about your sport – how to play it, how to train for it, how to compete - allows you to enjoy it to the full and gain most value from it. Being properly coached is also the key to success, over the next few weeks we just need to look over the river to see the power of coaching.
The Duchess of Cambridge tried her hand at judging a judo match - but stopped short of actually joining in with the contact sport
'Coach Core will offer 16 to 22 year olds the opportunity to become first class coaches, taught and mentored by professionals in their field and in turn passing these skills on to other young people. Once this year’s pilot scheme is successfully completed, we hope over the next few years to train hundreds, then thousands, of young people to become coaches - and in time, transform the sporting potential, aspiration and enjoyment of many thousands more across this Country.
'A special thank you to all those here today who have already signed up for the project. Catherine, Harry and I wish you every success in your new careers as sports coaches.'
Meanwhile, Prince Charles and Camilla were in Tottenham to watch torchbearer Scott Moorhouse, a Paralympic javelin thrower exchange the Olympic flame with Jay Kamiraz who ran the Olympic flame along Tottenham High Road past the remnants of a branch of carpet retailer Carpet Right that was burnt down during last year's riots.
The Olympic flame is making its way through the capital's Northern boroughs on day 68 of its journey around the UK before arriving in the Olympic Stadium on Friday evening for the Olympic Games.'
William and his brother were dressed equally casually - well, for male royals - in open neck shirts and chinos. Harry sported a distinctive patterned African belt and brown suede shoes. He walked onto the five-a-side football pitch where dozens of school children were practising shooting, dribbling and passing skills, and made two attempts on goal after running through a series of plastic cones.
He put the first shot 6ft wide and the second over the top of the bar. He later joked with one girl: 'Obviously it was the shoes.'
William and Harry asked a group of about a dozen boys and girls which team they supported. Many answered Arsenal or Chelsea. One boy told William he supported the duke's favourite team, Aston Villa, to which William replied: 'Good man, good man.'
Another boy said Xavi, the Barcelona and Spain midfielder, was the best in the world. William said: 'He is good, isn't he.'
William, Kate and Harry chatted to the young athletes before he made a speech emphasising how important sports coaching is
William took to the football pitch, while Kate showed her hand at table tennis and Harry played basketball
Kate looked the picture of summer perfect in a patterned white and beige Hobbs summer dress, low beige wedges and with her trademark blowdry
The Duke and Duchess of Cambridge and Prince Harry arrive at Bacon's College in Greenwich for the launch of a new sports project
In a short speech about Coach Core William jokingly likened himself to being a 'giraffe on ice skates' on the football pitch
Kate Middleton arrived by car with William at Bacon's College London
Kate wore a Hobbs dress and her favourite wedges whilst William went for a simple, yet smart look in a white shirt and black trousers
Prince Charles and Camilla jointTorchbearer Scott Moorhouse, a Paralympic javelin thrower, who exchanged the Olympic flame with Jay Kamiraz
Prince Charles, Prince of Wales watches at MENCAP Community Centre, Tottenham