Bowling? A 17 year old boy will have no interest in doing anything with adults. take him to a big branch of HMV or the Apple Store. The Imperial War Museum is pretty good for boys.
Camden Market Skateboarding at Cantelowes Park If there's anything good on: the i-Max cinema at Waterloo
Send him for an day on the East London line. He can check out the wonderful Geffrye Museum in Hoxton, the Whitechapel Gallery, explore the riverside at Wapping and Rotherhithe, take in the views from Crystal Palace and - if he's lucky - lose his virginity in Shoreditch on the way home.
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