|Created by||Frank Muir
|Country of origin||United Kingdom|
|No. of episodes||60|
|Running time||30 minutes|
|Original release||4 October 1956 – 27 December 1960
27 November 1971 – 26 February 1972
The series (in black and white) ran on the BBC from 1956–60 and (in colour) from 1971–72. Edwards took the part of Professor James Edwards, M.A., the drunken, gambling, devious, cane-swishing headmaster who tyrannised staff and children at Chiselbury public school (described in the opening titles as "for the sons of Gentlefolk"). The Edwards character bore more than a passing resemblance to Sergeant Bilko as he tried to swindle the children out of their pocket money to finance his many schemes.
The first six episodes were subtitled "Six of the Best". In 1959 a film was made based on the show, called Bottoms Up!. The series was revived in colour with updated scripts in 1971–72, slightly retitled Whacko!. In all, it ran for a total of 60 episodes, with 47 of black-and-white and 13 colour, of 30 minutes each. There were three special shorts. There was also a radio version, on the Light Programme, 45 episodes of 30 minutes broadcast from May 1961 – July 1963, with Vera Lynn starring as herself in the second episode. Many of these radio episodes were recovered by a BBC archivist from a listener's collection of tapes in 2012, and are now being broadcast on Radio 4 Extra.
- Professor James Edwards played by Jimmy Edwards
- Mr Oliver Pettigrew played by Arthur Howard in 1956–60 and Julian Orchard in 1971
- Mr F.D. Price Whittaker played by Kenneth Cope
- Mr S.A. Smallpiece played by Norman Bird
- Lumley (a pupil) played by John Stirling
- Mr R.P. Tench played by Peter Glaze
- Mr Halliforth played by Edwin Apps in 1956–60 and Peter Greene in 1971
- Parker played by David Langford
- Mr Forbes played by Keith Smith
- Mr Proctor played by Brian Rawlinson
- Mr Dinwiddie played by Gordon Phillot in 1956–60 and Harold Bennett in 1971
- Mr Cope-Willoughby played by Frank Raymond
- Matron played by Barbra Archer, Liz Fraser and by Charlotte Mitchell
- Taplow played by Gary Warren in 1971
- Potter played by Greg Smith in 1971
- Clodagh Rodgers appeared as herself during the colour series in 1972
- Max Bygraves appeared as himself in one episode in 1960 
- Vera Lynn appeared in one episode in 1959
Most of the show's episodes are missing, presumed lost. Six of the original black-and-white episodes are known to exist today; from the colour revival series of the 1970s, only one is known to have survived.
Only 7 episodes exist in the BBC TV archives, with 3 (out of the 6 remaining B&W episodes) having been rediscovered in December 2016.
- Series 3 episode 5 (21-10-1958)
- Series 5 episode 4 (01-12-1959)
- Series 6 episode 4 (03-06-1960)
- Series 7 episode 1 (22-11-1960)
- Series 7 episode 5 (20-12-1960)
- Series 8 episode 2 (04-12-1971)
- "Whack-O! Opening titles, BBC TV"". Retrieved 28 July 2008.
- Internet Movie Database, accesses 2014_02_13
- "Whack-O!", Kaleidoscope website