Bigger really is better for A-level students looking for a sixth form

Larger colleges are more likely to achieve better results, research finds

Small is definitely not beautiful when it comes to sixth-form provision, according to major research published today.

The analysis, carried out by the Association of Colleges (AoC), shows the smaller a sixth-form, the worse its exam results are likely to be. The findings call into question the Government's policy of encouraging schools and recently established flagship academies to provide post-GCSE education.

Today's data show that those with 50 or fewer pupils have an average score of 561 per candidate under the Qualifications and Curriculum Authority's scoring system. That is the equivalent of two C-grade passes and an E. Performance improves with size until those with more than 250 pupils – which includes most sixth-form colleges – score an average of 802, nearly three straight A-grade passes per pupil.

Martin Doel, the AoC's chief executive, said the disparity shows sixth forms with fewer pupils struggle to provide enough specialist teaching.

"Smaller sixth-forms are unable to provide the breadth of choice at A-level routinely offered by sixth-form colleges," he said. "[They] cannot match the variety and often lack expertise in key areas, such as chemistry, physics and geography."

The AoC's also found that more than 200 school sixth forms were unable to provide physics or geography at A-level, and 24 could not provide English.

Mr Doel added that the data suggest "new smaller sixth forms do not look like an efficient investment... particularly at a time when public spending is so constrained". The Government has tightened rules on schools' setting up sixth forms, requiring them to provide more evidence of the demand to establish them. But college bosses say civil servants "still seem wedded" to the original expansion policy.

The A-level league table produced by The Independent showed the top-performing sixth-form college this year was Peter Symonds in Winchester, Hampshire. Its 1,370 candidates were awarded the equivalent of just over three straight A grades each.

The top of the comprehensive schools' A-level league table was the JFS school in Harrow, north-west London, whose 225 pupils achieved an average of nearly three As each.