The Essex CSSE format is unique: a single combined English-and-Maths paper used exclusively by the four CSSE consortium grammar schools.
Where this format is used
CSSE papers are used by Colchester Royal Grammar, Colchester County High School for Girls, King Edward VI Grammar Chelmsford and Chelmsford County High School for Girls. Knowing which format your child will sit is the single most important fact to establish before buying a single practice paper, because format-specific practice is dramatically more useful than generic practice.
Paper structure & timing
The CSSE paper combines an English comprehension and writing component with a Maths component into a single sitting of around two hours. Marking is done by hand by the schools rather than by a national provider.
The combined format means children must switch between subject modes mid-paper, which adds a subtle stamina dimension absent from GL or CEM testing.
Question style & what it rewards
CSSE rewards strong written English alongside Maths fluency. The English component includes extended writing as well as comprehension, which makes it impossible to brute-force with reasoning practice alone.
The format rewards children who write fluently and at length under time pressure. A child who can produce three or four well-constructed paragraphs in twenty minutes has a meaningful advantage over one who can only manage one or two.
How to prepare for it specifically
Practise extended writing under timed conditions specifically. Pick a prompt, set a timer, and write — then redraft together the next day, focusing on sentence variety, paragraphing and vocabulary precision rather than length alone.
Use the CSSE sample papers provided by the consortium itself; generic 11+ comprehension is a poor substitute for the specific CSSE comprehension style.
Common myths about this format
A common myth is that CSSE is "easier" because it has no separate reasoning paper. In fact the writing component is unusually demanding, and the combined paper format adds stamina pressure that subject-discrete formats do not.
Practical recommendations
Practical recommendation: balance Maths topic work with deliberate, sustained English writing practice from Year 5 onward. Parents who treat the English component as an afterthought are repeatedly surprised by the proportion of marks it carries. Treat the format as a craft to be learned alongside the underlying subject material, not as a hurdle to clear once and forget about.