If you want to see some kids Lindy hop and then join in afterwards, the Shoreditch Festival is holding an evening musical performance, followed by the BBC Big Band. (Please note finishing time isn't stated on their webiste)

Details as follows:
From http://www.shoreditchfestival.org.uk/ugly.html


Sunday 24 August
The Big Band Youth Musical: Ugly Bugs Ball

6pm
Main Stage,
Shoreditch Park, New North Road
Free

Written by Elliot Davis and Sam Brookes in partnership with young people, and directed by Phil Wilmott.

Caterpillars of all ages will enjoy the world premiere of a new musical celebrating a special friendship between four young bugs as they dodge bats, birds and poison berries on a quest to earn their wings at the Ugly Bugs Ball.

It’s a boogie with the butterflies, a lindy hop with the lady birds and a wiggle with the earwigs that will get even a millipede tapping all 106 feet.

Prizes for kids in the best bug costumes!

Then join our heroes as they dance the night away to the music of the BBC Big Band: the UK’s leading big band and recent winner of Best Big Band Award at the 2007 British Jazz Awards.

Swing on by and dance until dark!