HOWZAT

The report said: “The combination of both higher than average expenditure per student and class sizes, is in part explained by the high annual duration of instruction time.”

It said the UK had among the largest class sizes in primary schools, with only Japan, Korea and Turkey having more children in lessons.

The report added: “In 14 countries there are 20 or fewer students per primary-level class. The OECD average is 21.5. The UK has an average 24.5 students per class.”

However class sizes at secondary level were lower than average.

The report said the pace of expansion in education - particularly at university level - was outstripping past projections and was expected to continue.

It had risen by nearly half in 10 years. While 37 per cent of teenagers in OECD countries went to university in 1995, that has risen to 57 per cent. This equates to eight million more students.

The UK boasts an above-average graduation rate, the report said, but has dropped from fourth to 12th since 1995 and is “likely to be surpassed” by other countries. Its drop-out rate from degree courses is also relatively high.

Mr Schleicher said the UK had recently devoted more of its GDP to education than any other country, and had one of the largest differences in salaries between graduates and non-graduates.

Graduates in the UK saw a 14 per cent return on the “investment” they had made in higher education (worked out by comparing the amount they had spent going to university with their salaries) - the fifth best rate out of 19 countries.

Many other countries were facing “tough decisions on funding and quality standards to ensure their education systems respond adequately to booming demand for degrees.” Funding for higher education was “barely keeping up with increased student numbers,” the report said.

Mr Schleicher said education could lose out to competing demands in ageing societies.

Civitas, the right-wing think-tank, criticised the Government over the OECD’s class size figures.

Anastasia de Waal, head of family and education said: “The government must finally commit to a proper class size reduction programme for infant classes if it wants to see real results. Cutting corners rather than class size is a huge mistake.”

A spokesman for the Department for Children, Schools and Families said: “Over the past 10 years we have seen steadily smaller class sizes and a better adult-pupil ratio thanks to our policies which see 150,000 more adults in classrooms. In 1997 there were 17 pupils per adult at primary level, now there are 12.”

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