Five Years of Growth and Change
Each block (year-group) in the school is referred to using a letter: the youngest boys enter the school in F block (Year 9), make their choices of GCSE subjects during that year before entering E block (Year 10), take their GCSEs at the end of D block (Year 11), and choose their specialist (sixth-form) courses before entering C block (Year 12). They either sit AS levels at the end of C block and complete their A levels at the end of B block (Year 13), or they take a Cambridge Pre-U course for the full two years and complete it at the end of B. In the days when some boys stayed on to apply for Cambridge and Oxford entrance after their A levels there was a further year, usually only consisting of one term, which was called A block. Once post-school entry procedures moved away from this pattern A block disappeared, but the nomenclature has never been adjusted to reflect that change.
There are thirty-five scheduled schools (lessons) per week in which formal teaching takes place, but some boys have one or more reading schools (free periods). Boys are taught in divisions (sets, classes, forms) normally containing about twelve boys of broadly similar ability in the case of specialists (the sixth-form) and about eighteen to twenty in the case of non-specialists (the first three years) although many divisions are smaller and some larger.
Each school lasts 40 minutes. There are seven on each Monday, Wednesday and Friday, five on each Tuesday and Thursday, and four on Saturday. Chapels and assemblies and tutorial groups occur on a timetabled basis every morning at 0835 until 0850; teaching begins sharply at 0900.
Because of the size of the school there are 10 minutes between all schools for boys to move around and arrive in time for their next lesson. There are no bells separating lessons; bells only ring to announce that chapels and assemblies are imminent.