Lang Lang is a busy boy - although 'boy' is a little unfair these days: the most renowned classical music performer of his generation, more rock star than concert pianist, he is now 29 years old. He looks younger, but feels a lot older - the result of eloquence and professionalism beyond his years, and because he has been in the spotlight since his teens and so seems to have been around forever. Over the years, Lang has performed with most of the world's best-known orchestras, packed out venues from Beijing's Great Hall of the People to New York's Central Park, and was seen by the biggest audience of all when he played at the opening ceremony of the 2008 Olympic Games in Beijing. A 2009 Time magazine article named him among the 100 most influential people in the world. His youth, however, hasn't stopped him enthusiastically warming to a role usually associated with those slightly older: mentor to the next generation of musical talents. That's why the Shenyang native is to be found recently in a function room at the Langham Place hotel in Mong Kok, patiently and humorously passing on tips to some talented young pianists. Lang is hosting a masterclass with three of Hong Kong's most promising junior musicians - 11-year-old Thomas Chan, 10-year-old Kate Lee and eight-year-old Li Zhongxin, a third-grader at Hong Kong Yew Chung International School and inaugural winner of the Langham Lang Lang Scholarship, which aims to recognise and nurture the city's musical talents of the future. Lang was involved in the judging. (The similarity in names between Lang and the hotel group for whom he is global brand ambassador, he says, is a coincidence - although, he jokes, he was asked by his taxi driver on a recent arrival at the group's property in London: 'Is that your hotel?') It's far from being the first time Lang has involved himself with such a project. So seriously does he take the job of evangelising classical music and supporting the stars of the future, and so obviously does he relish doing so, that in 2008 he created the Lang Lang International Music Foundation. 'I started my foundation with the aim of helping the next generation of exceptional musical talents around the world,' he says. 'I've done a lot of work on that in the US and Europe, and now it's time to extend it to Asia.' He's also about to launch his first school: Lang Lang Music World in Shenzhen and Chongqing. He fits all that in alongside charitable work, including a role as a Unicef goodwill ambassador, commercial commitments and, of course, a hectic, globetrotting tour schedule. 'I'm quite energetic,' he says before the Hong Kong event, with admirable understatement. 'I rest for eight hours a day and I spend the rest of the time doing something. It's pretty crazy but it's fun.' Even without the scholarship, his influence is already making itself felt in his homeland, with China producing a huge proportion of the world's promising young musicians in an explosion in interest in classical performance that some have dubbed 'the Lang Lang effect'. The artist, however, modestly prefers to rationalise it as the result of demographics. 'There are 40 million kids learning the piano, 20 million learning the violin,' he says. 'The numbers are extremely high.' But you can see the Lang Lang effect in other ways. It's there at the masterclass, where the mannerisms of scholarship winner Zhongxin are those of a Lang Lang Mini-Me, in particular the elaborate hand gestures for which the pianist is noted (and occasionally mocked). You can also see something else at the masterclass: Lang Lang's love of and commitment to teaching. He's a natural teacher: informative, relaxed, helpful and witty - 'I know you don't drink, right?' he asks little Zhongxin in response to some rather unsteady phrasing (by the end of the class, he's playing with vastly improved pacing, passion and confidence). The artist is utterly immersed in the music, humming along with cheerful enthusiasm - and woefully flat - before apparently catching himself in the act and apologising for being such a bad singer. In spreading the word about the joys of playing music, he says, he's not just focusing on the Lang Langs of the future. 'I don't think everyone wants to be a professional musician. It's a nice way to build up a hobby, and to learn discipline and creativity.' He sees his mentoring not so much as an optional add-on as a responsibility for someone in his position. 'For me, being a human being, it's not just about playing concerts,' he says. 'It's important to be professional, but we also need to share out our time, and remember the reasons that inspired us to be musicians. I think that's just as important as doing good concerts.' Accordingly, he admires his idols as much for their contribution to the popularisation of music as their musical skill. 'I have a high respect for people like Leonard Bernstein,' he says. 'He basically created young people's concerts in the 60s and 70s; he had a huge impact on US musical life. But Bernstein was unusual. A lot of great artists are focused on the concert world only.' From his own storied performing history, he picks out not an obvious highlight such as the Olympics as his most memorable show, focusing instead on concerts from his formative period. 'My first performance at Carnegie Hall was very meaningful,' he says. 'I was 18. But the one that really launched my career was with the Chicago Symphony Orchestra in 1999.' Hitting the big time so young means Lang has had to do a lot of his growing up in public, amid the white noise of critical feedback, and has developed the habit of not reading about himself. 'I don't read the critics. There are so many articles, blogs, Twitter, Facebook - if you focus too much on trying to read all of it, you lose a sense of yourself.' Instead, he says, improving as a performer is a gradual, cumulative process. 'My style of playing doesn't really change, but getting more knowledge, more information, more different interpretations is truly necessary - and these things don't come overnight.' Back at the masterclass, Lang watches as an extension is fitted to the piano so the miniature maestros can reach the pedals. 'You know, I never had that when I was growing up,' he recalls. 'I had to stand up to give performances when I was young.'