Kate wore an outfit by Luisa SpagnoliCredit: Ian Vogler The engagement is part of a series of events the Duke and Duchess are undertaking – many with Prince Harry – to promote the royal trio’s Heads Together mental health campaign.Heads Together is a umbrella organisation – with Place2Be a member – that aims to change the national conversation around psychological issues to a positive one. The Duchess of Cambridge has said she wants to teach her children the importance of respect, honesty and kindness.Kate said making Prince George, the future King, and his sister Princess Charlotte aware of the value of these qualities was just as important as academic or sporting success.The Duchess’s comments came as she celebrated pupils with the “K factor”, or kindness factor, during a visit to Mitchell Brook Primary in north-west London with her husband the Duke for the launch of Children’s Mental Health Week.The annual event – which this year has the theme Spread A Little Kindness – is an initiative founded by the mental health charity Place2Be, which has Kate as royal patron, and runs counselling sessions at Mitchell Brook in Neasden. The Duke and Duchess of Cambridge sit down on a “kindness bench” as they celebrate the efforts of school children with the “K factor”Credit:Ian Vogler/PA Wire Kate, who wore an outfit by Luisa Spagnoli, said: “My parents taught me about the importance of qualities like kindness, respect, and honesty, and I realise how central values like these have been to me throughout my life.”That is why William and I want to teach our little children George and Charlotte just how important these things are as they grow up.”In my view it is just as important as excelling at maths or sport.” The Duchess of Cambridge arrives at the Mitchell Brook Primary School, north London, where she and her husband are attending the Place2Be Big Assembly with Heads Together for Children’s Mental Health Week.Credit: PA Wire/PA Images/John Stillwell Speaking during a special school assembly where those with the K factor were recognised, the Duchess added: “People often ask me why I am so interested in the mental health of children and young people.”The answer is quite simple – it is because I think that every child should have the best possible start in life.”When I was growing up I was very lucky. My family was the most important thing to me.”They provided me with somewhere safe to grow and learn, and I know I was fortunate not to have been confronted by serious adversity at a young age.” At the weekend, Kate, William and Harry competed in a relay race at the Queen Elizabeth Olympic Park in east London, where they joined around 150 London marathon competitors who are fundraising for the eight Heads Together charity partners or the campaign itself. Among the competitors was The Telegraph’s Bryony Gordon, who shared a warm moment with Prince Harry when she was discussing the challenges of mental ill health with news reader Sian Williams. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.