Ideas for cheap but fun things to do for 15 year old girls in London?

[Miladymilord]

during the day/early evening

They will be shopping and eating but I'd like to do something with them to make it more interesting! We'll be in central London

www.lonelyplanet.com/england/london/travel-tips-and-articles/top-20-free-things-to-do-in-london/40625c8c-8a11-5710-a052-1479d277d4a5

London Design Biennial at Somerset house?

Camden Market will appeal to most 15 year old girls

Yes I was thinking of Camden. Is it still a cool place to go (it was cool about 40 years ago when I last went )

Bit of culture? Tate Modern is free and the new [ish] Switch House tower has a viewing platform with outstanding views over to St Paul's, the City and the Thames.
Lots of other stuff to see on the South Bank.
River bus between there and Tate Britain is not too spendy, and offers a different view of London.

I think we'll stay north ish, we've done the south Bank to death. Camden is a good shout as we can then go to primrose Hill and maybe the Harry Potter shop at King's Cross (she loves Paddington and Harry Potter )

Maybe we bumped into each other 40 years ago in Camden? I'm sure you know but, if you go to Camden market, stick to the canal side and Stables area. The first part nearest the tube is rubbish. The Harry Potter shop at Kings X seems to have queues but it always looks a lot of fun. In fact, if I were you, I'd just go to Kings X and St Pancras, forget Camden

I was thinking of a canal boat trip from little Venice to Camden?