More or Less was broadcast on Tuesday, 17 December, 2002 at 1600 GMT on BBC Radio 4.

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As the Government explores the idea of value-added league tables for schools, More or Less looks at how we measure the difference a school can make.

We examine the latest research which used computer models to send virtual pupils to simulated schools.

The conclusions of the mathematicians who ran the model include the unsettling one that even if all schools were equal at the start, the publication of league tables themselves would cause some schools to rise and some to fail.

And the music which is written entirely in numbers. The large scale version takes quite a few people to play it and they each play one note repeatedly.

Part of the bell ringing solution

Bell-ringing composer Colin Wyld found the solution to an 150 year old problem - how to compose a Stedman Triples using only bobs.

It is an achievement for which he is famous within the bell-ringing community

Producer: Michael Blastland
Editor: Nicola Meyrick