Previously known as Autumn Leaves, the six-part comedy series has been written by Walliams with writing team The Dawson Brothers - Tim Inman, Andrew Dawson and Steve Dawson - and will begin filming "within the next few weeks" in Greater London.
The BBC describe the show as "a comedy about a dysfunctional staff room, unrequited love and interactive white boards".
Walliams, as was already known, will head the cast as lovelorn chemistry teacher Mr Church; the object of his affections is new member of staff Miss Postern (Catherine Tate), a French teacher who has never actually visited France.
Life On Mars star Philip Glenister will play Mr Gunn, a "lothario gym teacher" who also has his eyes set on Postern, whilst acting legend Frances De La Tour (Rising Damp) will take on the role of Greybridge School's no-nonsense, plain-speaking headmistress, Ms Baron.
The line-up is completed by Joanna Scanlan (Getting On) as nosey drama teacher Mrs Klebb; Steve Speirs (Stella) as Mr Barber, the pessimistic geography teacher who's counting down the days until he can retire; and Daniel Rigby (Eric & Ernie) as a mod-like music teacher who desperately wants to be mates with the kids and still clings to his dream of becoming a rock star.
Executive producer Mark Freeland, head of the BBC's comedy department, says: "Led by David Walliams, it's an absolute privilege to work with such a brilliant cast and off-screen production team. Like my Latin GCSE, nothing can go wrong. At least that's what I thought at the time."