The Crucible Incident
From BRGS Wiki
The Crucible Incident refers to the time Mrs Sellens (along with some other members of the English Department), apparently being unable to read a course specification, taught a Year Eleven group Arthur Miller's The Crucible for four months without realising it was no longer on the syllabus. This caused great embarrassment to all concerned, and is often cited as one of the reasons why Mr Patrick lost his job.