Pleased with his work on "Little Plum" and "Minnie the Minx", Beano editor George Moonie asked Baxendale to create a third feature for the comic. Inspired by a picture that Baxendale had sent to the comic beforehand (and since forgotten about), Moonie suggested a strip entitled When the Bell Rings consisting of two or three small panels and a final, large panel with a crowd scene, depicting a horde of children leaving school.
The Bash St Kids concerns the misadventures of Class 2B of Bash St School and their cast of supporting characters - notably Teacher (who still wears a mortar board even now, decades after they disappeared from most establishments), the Headmaster (likewise), Olive the dinner lady, the Janitor and Winston the school cat. The kids themselves are: Danny (sometimes called Deathshead Danny because of his distinctive skull & crossbones shirt), Smiffy, Spotty (whose name may actually be Jasper), the myopic 'Erbert, Wilfrid (he of the face obscuring jumper), the twins Sidney and Toots, Fatty, and Plug, though in early strips a huge cast of mostly unnamed kids (the exceptions being Teddy, Jimmy and Ella, though Jimmy may actually have been Smiffy) appeared, with most of the more familiar current cast coming later. There are also a couple of irregular members of the class - Teacher's pet Cuthbert Cringeworthy and Wayne (the latter created as part of a reader's competition: Wayne was perpetually injuring himself). In a run of text stories in The Wizard, some of the characters were given full names: Danny is Daniel "Deathshead" Morgan, Smiffy is James Smith, Sidney is Sidney Pye, Toots is Kate Pye, Plug is Percival Proudfoot Plugsley, Fatty is Fatty Fudge. Spotty didn't get a full name here as he was yet to make his debut. Teacher's real name is apparently Algernon, while his wife (who looks exactly like him, even down to the moustache) is only ever referred to as 'Mrs Teacher'. Plug got his own comic in 1977, which revealed his full name to be Percival Proudfoot Plugsley.
The first "When the Bell Rings" strip appeared in The Beano issue 604, dated 13 February 1954, and had a winter scene. D.C. Thompson did not provide a script and so Baxendale wrote it himself. The strip was renamed The Bash Street Kids in 1956, and underwent a number of changes: the brief story-structure and emphasis on crowd scenes were replaced with something more conventional, and the horde of anonymous children was whittled down into a smaller cast of specific characters (although two of these characters - Toots and a then-unnamed Danny - appeared in the very first strip). It has become a regular in the comic, featuring in every issue.
Baxendale drew the strip until 1962, when David Sutherland replaced him, initially in a similar style, but simplifying it later in the decade. Sutherland has drawn the majority of the strips since then, except for a period from 1999 to 2000, when Nigel Parkinson took over. The strip has also had a number of ghost artists, including Gordon Bell in the early 1970s, John Sherwood later on in the 1970s, Keith Reynolds in the 1980s and Tom Paterson in the early 1990s. In recent years, Mike Pearse and Kev F. Sutherland have also occasionally drawn the strip.
Like many long-running UK comic strips, The Bash Street Kids is anachronistically frozen in the era in which it began. It portrays Class 2B of Bash Street School, Beanotown, where the teacher and headmaster still wear mortar boards and gowns and pupils sit at wooden desks with inkwells. They are taught by a stereotypical teacher, who is known as "Teacher" (his wife is called "Mrs Teacher"). The ten regular pupils are:
- A Very Funny Business, 1978, p.9