What is CEM?

Most parents researching grammar schools encounter two names: GL Assessment and CEM. GL is the more familiar of the two, but CEM — the Centre for Evaluation and Monitoring — is used across a wide range of areas and has a distinct philosophy that shapes how children should prepare. If your local grammar schools use CEM, understanding what that actually means in practice will help you plan sensibly from the start.

CEM is a research unit based at Durham University. Unlike GL Assessment, which is a commercial publisher, CEM comes from an academic background and was designed with a specific purpose: to create a test that's harder to tutor for. The idea was to produce something that measures genuine reasoning ability rather than a set of practised techniques. Whether it fully achieves that is debated — but it does mean the test feels different from GL, and preparation needs to reflect that.

Areas that currently use CEM include parts of Birmingham, Buckinghamshire, Berkshire, and Wiltshire, among others. Coverage changes over time as local authorities and individual schools review their arrangements, so it's worth confirming directly with the schools you're targeting which exam board they use. Don't rely on information from a previous year's parent group — check the school's own website or contact their admissions team.

The CEM test covers three broad areas: Verbal Reasoning, Numerical Reasoning, and Spatial Reasoning. What makes it unusual is the format. Questions are not separated into tidy sections by subject. Instead, they shift rapidly between topics — a child might move from a word analogy to a number sequence to a spatial pattern within the space of a few minutes. Children sitting the exam often can't tell which subject area they're in at any given moment. CEM typically involves two sittings rather than one, both taken on the same day or across a short window. The pace throughout is fast.

This mixed, unsectioned approach is deliberate. A child who has drilled one question type extensively won't find the same comfort they might in a GL paper, where they can settle into a familiar rhythm. CEM asks for instinctive reasoning — the ability to switch mental gears quickly, to read a question type and respond without hesitation. That's a different skill from pattern recognition built through repetition, though the two aren't entirely separate.

The common reaction from parents who hear this is either relief or alarm. Relief, because it sounds like the test is on their child's side — more about natural ability, less about months of drilling. Alarm, because if you can't practise for it, what are you supposed to do? The truth sits somewhere in the middle. Children absolutely benefit from structured preparation for CEM. It just looks different.

Rather than mastering a catalogue of specific question formats, preparation for CEM is better focused on building the underlying reasoning capacity those formats draw on. That means broad reading — genuine reading for pleasure, at a good level of challenge — to build vocabulary and comprehension instincts. It means mental arithmetic practised until it's quick and automatic, because slow calculation costs time the test doesn't give. It means timed practice from Year 5 onwards, not to rehearse specific question types but to build the habit of working accurately under pressure. Less drilling of formats, more building of genuine understanding.

Spatial Reasoning is where CEM differs most sharply from GL's Non-Verbal Reasoning papers. Both involve shapes and patterns, but CEM's spatial questions can feel more fluid — less about a learnable set of transformations, more about holding a shape in your mind and reasoning about it. Children who enjoy puzzles and visual thinking often find this the most engaging part of the test. For children who find it harder, practising with 3D shapes, tangrams, and pattern-based puzzles over time genuinely helps.

If you're comparing CEM and GL directly — perhaps because your area gives you a choice, or you're weighing up schools from different catchments — the key distinction is consistency of format. GL papers follow predictable question structures within each subject, making targeted practice highly effective. CEM is less predictable by design. Neither is harder in an absolute sense, but they reward different kinds of preparation. You can read more about what GL Assessment involves in our guide to GL Assessment.

The most useful thing you can take from all of this is that CEM preparation is not a matter of doing nothing and hoping natural ability carries the day. It's a matter of building the right kind of capability — flexible, fast, confident reasoning across verbal, numerical, and spatial domains. Start in Year 5, keep sessions varied and relatively short, and make sure your child is building genuine understanding rather than surface-level familiarity with a handful of question types.