GL Assessment vs CEM: What's the Difference?

If you are beginning to research the 11+ exam, you will quickly encounter two names: GL Assessment and CEM. These are the two main organisations that provide 11+ tests to grammar schools and local authorities across England and Northern Ireland. Understanding the difference between them is essential — because the right preparation for one is not the same as for the other.

Who Uses Which Test?

Different areas and schools use different providers. The Trafford Consortium uses GL Assessment, which is why ElevenPilot focuses specifically on the GL Assessment format.

Other areas using GL Assessment include parts of Kent, Hertfordshire, Buckinghamshire, and many individual grammar schools. CEM is used in areas including Birmingham, Warwickshire, Durham, and others. Some areas have moved between providers over the years, so always check directly with your target school which test they currently use.

GL Assessment: Key Features

The GL Assessment format is characterised by:

Clearly defined question types

GL Assessment papers use established, consistent question types that appear year after year. Synonyms, antonyms, hidden words, letter sequences, shape series, shape analogies — these formats are well-known and can be practised directly. This means preparation for GL Assessment is very targeted: learn the question types, practise them, build speed.

Three separate papers

GL Assessment typically uses three separate papers: Verbal Reasoning, Mathematics, and Non-Verbal Reasoning. Each tests a distinct skill set, and children sit them in separate sessions.

Multiple choice format

Most GL Assessment questions use multiple choice answer formats, usually five options. This means children can use elimination strategies and educated guessing when uncertain.

Speed is critical

GL Assessment papers typically contain a large number of questions relative to the time allowed. Verbal Reasoning papers often have 80 questions in 50 minutes — less than 40 seconds per question. Speed and automaticity are as important as understanding.

CEM: Key Features

CEM (Centre for Evaluation and Monitoring, part of Durham University) takes a different approach:

Deliberately varied format

CEM tests are designed to be less predictable and harder to coach for. Question types vary and are not published in advance. This makes specific question-type preparation less straightforward.

Combined papers

CEM typically uses two combined papers, each mixing verbal skills, numerical reasoning, and non-verbal reasoning questions. There is no single "Verbal Reasoning paper" or "Maths paper."

Greater emphasis on literacy

CEM papers tend to include more extended reading and more complex vocabulary work than GL Assessment. Strong readers often have an advantage.

Cloze tests

CEM often includes cloze procedure questions — passages with missing words that must be completed. This format does not appear in GL Assessment.

Which is Harder?

This is a question with no simple answer. Different children find different tests harder depending on their strengths. Children who are strong readers and less comfortable with structured question types sometimes prefer CEM. Children who respond well to clear formats and benefit from targeted practice often perform better in GL Assessment.

What both tests have in common is that preparation makes a significant difference — and that the best preparation is consistent, focused, and specific to the format being sat.

Can You Prepare for Both?

Some families whose children are applying to schools using different test types need to prepare for both. The core underlying skills — vocabulary, reading comprehension, logical reasoning, mathematical fluency — are shared. The format-specific elements require separate attention for each test type.

If your child is only applying to Trafford Consortium schools, focus exclusively on GL Assessment preparation. Spreading preparation across both formats dilutes effort and is unnecessary.