SCOTTISH pupils’ ranking in mathematics in a key education international comparison study is at risk of falling if school hours are not extended by six hours a week to make up for lost lessons during lockdown, according to a leading academic.

Professor Lindsay Paterson issued his warning as 15-year-old pupils prepare to sit tests next spring set by the Programme for International Student Assessment (PISA). The results will be published the following year.

He pointed out that having missed more than three months of classroom lessons from March to June many children would not have reached the expected level and would be unable to do so by the time of the international assessment exercise without extra classes.

Primary and secondary schools closed to all pupils in Scotland on March 20 in a bid to help reduce the spread of the coronavirus and save lives. Since then some teachers have set work for pupils digitally with parents expected to help with home-schooling.

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However Paterson, who is professor of education policy at Edinburgh University, said research had shown that parents are best able to help their children with reading and literacy tasks but least equipped to help with maths.

He said the lack of classroom teaching in maths was likely to become apparent when pupils sat the numeracy PISA tests.

“Scotland has struggled in PISA since around 2000 or 2003. The Scottish PISA results could get worse if pupils don’t get the extra six hours a week lessons,” he said.

“Research that has been done on previous school closures based on what happens during the summer holidays found that parents are better at teaching their children literacy than teaching numeracy or mathematics.

“The main topic of the 2021 PISA will be children’s mathematics and this is potentially one of the areas hardest hit by the prolonged period of school closure.”

He added that while almost all countries have shut schools, though Sweden’s had not closed, one issue would be how well they have responded to the crisis and put measures in place to enable children to catch up with what they have lost.

“That’s why the policy on catch up is so important,” he said.

Paterson is a member of the Commission on School Reform set up by the think tank Reform Scotland which last week published a report calling for the school week to be extended by six hours over a two-year period to allow pupils to catch up.

The £200 million proposal by the group, which is made up of current and former head teachers, education professors and chaired by former director of education in Clackmannanshire, Keir Bloomer, warned that “there is an urgent need to plan for catch up of the lessons lost”.

It suggested an estimated 19,000 additional staff would be needed to oversee the catch-up sessions, which could be made up of retired and trainee teachers, plus university students from other disciplines.

The report warns that “pupils will have gone 21 weeks without proper schooling”, adding that “inequality will have worsened”.

The PISA study is designed to examine how 15-year-olds can apply what they have learned in school to real-life situations. It is not definitive and the system has many critics within education, but it offers one way of comparing the education systems in different countries and can influence policymakers.

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It was set up in 2000 among countries from the Organisation for Economic Co-operation and Development (OECD). Some 600,000 pupils from 79 countries take part in the tests.

The PISA study for 2018, published last year, found Scotland’s performance in maths had slipped by two points (491 down to 489) against 2016 – the figure was behind both England and Northern Ireland. Across the world Scotland was ranked 31st for maths.

Scotland’s performance in the PISA data published in 2016 caused a political row, with Scotland was classed as “similar to the OECD average” in maths, science and literacy for the first time.

At the time, Education Secretary John Swinney said the results made for uncomfortable reading and showed that radical reform was needed.

Responding to the call for the school week to be extended, a Scottish Government spokesman said: “We know pupils will need extra help when schools re-open. We are investing an additional £100m over the next two years to tackle the impact of lockdown and ensure children get the support they need, and we are currently considering a range of options on how best to deploy this.

“For those who don’t have the technology at home to learn effectively, we are supplying for 25,000 laptops or tablets – with internet access provided – for disadvantaged children to support learning outside school. This is the first phase of our £30m commitment to support a roll-out of digital devices to disadvantaged children and young people.

“Reducing the poverty-related attainment gap remains a defining mission for the Scottish Government. In addition to the £182m to be invested in the Scottish Attainment Challenge this year, we will be working alongside partners to increase support to those families and communities who need it most.”