Ends 8.15.

Chuck Finn
A glitch in the time continuum results in Fingers being usurped by a distant relative from the 40th century. (R) (S)

7.25 Histeria
Attila the Hun, Napoleon Bonaparte, Sigmund Freud, Alexander the Great and Cleopatra all feature in the animated whistle-stop tour through history. (R) (S)

7.45 Blue Peter
A look at the history of May Day. With sign language. Shown yesterday at 5pm on BBC1 (S) (W)
WEBSITE: [website removed]
BBC BLUE PETER MAGAZINE: £1.85. New issue on sale 1 May

Ends 10.50.

Andy Pandy
Double bill. Andy blows a bubble that follows him all over, and Teddy tries making a kite from a flyaway sheet.

8.25 The Story Makers
Milton and friends discover what lies at the end of the rainbow.

8.40 Clifford the Big Red Dog
The denizens of Birdwell Island learn not to make assumptions before knowing the facts.

9.00 Teletubbies
Double bill. Tinky Winky, Dipsy and Laa-Laa play a "who did it?" game, then Po has a rest after a scooter ride. BBC VIDEO: Teletubbies 2 video boxed set. price £12.99

9 50 Playdays
Peggy Patch and her friends have a party in Peggy's tea shop.

10.10 Tweenies
Double bill. The Tweenies try curing Doodles of his cough, then Milo loses one of his socks.

Repeats are not indicated.
10.50 Hotch Potch House (ages 3-5) Babies 6333227
11.10 Look and Read (ages 7-9) Captain Crimson: Banana Drama - Captain Crimson is taken hostage during a bank raid. 9881024
11.30 Zig Zag (ages 7-9) Weather: Wind - with BBC weather presenter Helen Young. 6191685
11.50 Landmarks (ages 9-12) Britain since 1930: the Blitz - recalling the wartime hardships of April 1940. 9983666
12.10 Focus (ages 9-11) Citizenship: Minorities - Black and British - three children from minority groups talk about their experiences of racism.

Business updates, with Adrian Chiles and Adam Shaw.
Ceefax: page 238

An appeal for Farm Africa. For donation details see Sunday at
5.20pm on BBC1

As the semi-finals get under way, Ray Stubbs , Hazel Irvine, Steve Davis and John Parrott introduce the initial action from the best-of-33-frames matches at the Crucible in Sheffield.
At this stage last year, Ronnie O'Sullivan overcame Joe Swail 17-11, while, in a nerve-wracking encounter, 1998 champion John Higgins eventually eclipsed the challenge of finalist Matthew Stevens by 17 frames to 15. The winner of each match this year will be guaranteed a cheque worth at least £152,000.
WEBSITE: www.bbc.co.uk/snooker
Including at 3.20 News; Regional News (Digital: BBC London News); Weather

Much Apu about Nothing. Marge and Homer's support for a proposal to deport illegal immigrants from Springfield is tested when they find that Apu's visa has expired. With the guest voice of actor Joe Mantegna.

Someday Your Prince Will Be in Effect (part 1). Will and Carlton compete to get a date for Hilary's fancy-dress party. The story concludes tomorrow at 6.20pm.

The opening exchanges at the Crucible theatre, Sheffield, of the second semi-final at this year's world championship. Introduced by Ray Stubbs.

The Village in the Stones. The Wiltshire village of Avebury - a British World Heritage site - was built in Neolithic times and boasts Europe's largest stone circle. Alexander Keiller , a millionaire playboy and fanatical historian, restored the site in the 1930s, but his methods were controversial.
Film from the time of the intervention has recently been found, and here elderly Avebury residents recall how
Keiller divided their village both physically and emotionally. Director Jenni Mills ; Producer David Parker First shown in BBC West 89 WEBSITE: www.bbc.co.uk/homeground

Two teams of motorists compete to transform a normal car into an extraordinary machine on a L2,000 budget in this new seven-part series presented by Trevor Nelson. Dune Racer. The first two teams' mechanical ingenuity and driving ability are tested over three days as they try turning hearses into speed machines and then race them across sand dunes. While the losers' vehicle is crushed, the prize awaiting the winners is the drive of a lifetime.
Director Ewan Keil ; Series producer Andy Francis

Continuing coverage of the second semi-final. The two competitors are just a maximum of four sessions away from securing a spot in Sunday's final. Presented by Hazel Irvine, Steve Davis and John Parrott.

Presented by Jeremy Paxman.

Keith Wood and Jonathan Davies look back at last weekend's European Cup semi-finals and discuss the ongoing Premiership relegation battles. Plus reports from John Inverdale , Eddie Butler and Nick Mullins. Director Stephen Potter : Editor Jo McCusker

Cassocks for Council Estates. In an episode of the job-swap series, two men of the cloth whose parishes lie in vastly differing areas exchange working environments for one week. Narrated by Jamie Theakston. Director Richard Bond ; Series producer Hilary Rosen

Repeats are not indicated.
Open Science 12.30 Final Frontier 2124241 1.05 Lab
Detectives 3691203 1.20 What Have the 1960s Ever Done For Us? 1396406 1.30 Catching the Good Health Train
19203 2.00 Did Tibet Cool the Earth? 72845 2.30 Volcanos and the Atmosphere 84680 3.00 Biosphere 2 Curriculum Development 3.30 Teaching Today ICT: Higher Order Skills in the Secondary School
Languages 4.00 Espana Viva (parts 9-10)/Spanish Globo
(parts 1-2) - language lessons plus Spanish animations. Working in Engineering 5.00 Troubleshooting
Open University 6.00 The Art of Breathing 22208 6.30 Food: Whose Choice Is It Anyway?