The existing exam system is unable to distinguish between test performance and knowledge and does not lead to genuine progress, according to a leading educationalist.

A new approach is needed to restore trust in exams and promote teaching that improves achievement rather than test results, says Daisy Christodoulou, research and development director at the Ark academy chain.

Writing in this week’s TES magazine, Ms Christodoulou, author of the book Seven Myths About Education, says that although exams provide valuable information, “the way they are currently used is hugely distorting”.

Tests are being used to indicate how much students know by sampling a small part of that knowledge, she writes. This encourages teachers and students to focus on the elements that are likely to come up in the test, at the expense of a wider body of knowledge.

“Our test-based accountability system has incentivised teaching that doesn’t actually lead to genuine educational gains, resulting in methods that can loosely be defined as ‘teaching to the test’.”

The idea that improvements in test scores equate with increased achievement is often untrue, she adds.

Ms Christodoulou cites research from the US which shows that performance in high-stakes tests is not replicated when students are given different assessments on the same body of knowledge, suggesting that they are being prepared for a particular test rather than given a deep understanding of the subject.

“If we rely on this approach, test scores will go up but they won’t mean what we want them to mean,” she writes.

Read the full article in the 19 December edition of TES on your tablet or phone or by downloading the TES Reader app for Android or iOS. Or pick it up at all good newsagents

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