1.2 Scores, Age Standardisation & School Decisions

Understand what the score compares

The Common Pre-Tests report Standardised Age Scores (SAS) to senior schools. ISEB describes a comparison with a standardisation sample from the independent-school sector, with an average of 100. Calling this the average of all children nationally would describe a different population. A standardised score is also different from a percentage: a score of 100 does not mean 100% correct.

Age standardisation supports comparison between applicants of different ages and applicants taking the tests at different points in the session. It is not a fixed bonus added to every summer-born pupil. Families cannot calculate the adjustment simply by counting the months between two birthdays. Enter the correct date of birth and let the test's scoring system perform the adjustment.

The current official sources used here do not provide a public raw-mark-to-SAS conversion table, a universal school admission cutoff or a guaranteed maximum score for families to target. Use current information from the relevant school when discussing its admissions criteria.

Raw marks, percentages and standardised scores

A raw count says how many answers were correct. A percentage relates a correct count to a question total. A standardised score expresses performance on a comparison scale. These measures answer different questions, so keep their labels visible whenever you discuss results.

For an ordinary practice sheet, 18 correct answers out of 24 gives 75%. That calculation is useful for reviewing that sheet. It does not provide an ISEB SAS of 75 or show that the pupil has passed. Another child completing a different sheet may have met easier or harder questions. Even equal percentages do not establish equal attainment when the question sets differ.

There is no universal pass mark

ISEB's support guidance says these tests have no grades or pass mark of their own; decisions depend on the school using them. Ask schools how the tests fit into their admissions process. A school may also request references, reports, interviews or other assessments. Follow that school's published requirements rather than assuming every school uses the same sequence.

An offer, an invitation to a further assessment and a reserve-list decision are different outcomes. A practice score cannot guarantee any of them. Equally, finding several practice exercises difficult does not establish that a child is unsuitable for a particular school. Use specific learning needs and direct school advice to plan the next step.

Worked interpretation example: A child answers fewer questions than a friend and feels worried. The useful response is to recognise that adaptive question counts can differ. Ask whether the child read carefully, followed instructions and raised any technical problems. Counting questions after the event cannot reconstruct the official score.

Who receives the results?

Senior schools can access results through their Senior School Portal. ISEB lists subject SAS information and other report measures, including stanines, percentile ranks, group ranks and mean SAS. A percentile rank concerns position within a comparison group; it is not the percentage of questions answered correctly. A mean SAS is a summary of scores, not a replacement for understanding the subject profile.

ISEB does not release Pre-Tests results directly to parents. Its advice is to ask the senior school for context. Schools control what feedback they provide. A family should not expect a numerical score report to arrive automatically in the Guardian Portal, and this guide does not promise that schools will disclose their internal decision criteria.

Use practice results to choose teaching

Keep a short error record with four columns: topic, what happened, corrected method and next practice action. This turns practice into information you can use, without trying to imitate official psychometrics.

• Knowledge gap: A pupil does not know that a percentage means parts per hundred. Revisit representations before adding time pressure.
• Method gap: They understand a fraction but add its denominator. Use equal-sized parts and a common denominator.
• Reading slip: They calculate the amount sold when asked for the amount remaining. Underline the requested quantity.
• Checking gap: They identify one correct pattern feature but ignore another. Check both before submitting.

Compare later work with earlier work on similar skills and conditions. One short set is a small sample; look for a recurring difficulty before changing the whole study routine. Record whether a question was answered independently or with a hint, because those are different learning stages.

A balanced conversation after the tests

Let the child describe the experience without asking them to reconstruct protected live questions. A useful conversation focuses on comfort, instructions and any incident that should be reported. Avoid turning remembered question difficulty into a forecast of success or failure.

For admissions interpretation, contact the relevant school. For a registration or testing incident, use the centre and ISEB's support channels. For learning, return to a concrete skill: understanding a paragraph, subtracting accurately, testing a code or tracking a reflected shape.

Sources checked 18 October 2026: ISEB's scoring description and ISEB's guidance on parents' access to results.