NICOLA Sturgeon put her neck on the line by labelling it her “defining mission”, but uncertainty remains whether the attainment gap can be eliminated by the 2026 original timescale, if at all.

The First Minister has been blighted by her struggle to eradicate the education gap between Scotland’s poorest and richest children.

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Ms Sturgeon has repeatedly been criticised by her political opponents over her failure to keep a pledge to eliminate the poverty-related attainment gap.

The latest stats, published in December, shows the gulf between the achievements of pupils in the least deprived areas and their peers in the most deprived areas remained wider than in 2018/19, before the pandemic hit.

Her political foes have framed her being more concerned with independence instead of focusing on key domestic issues, most notably education.

The intention from Ms Sturgeon was there from the get-go.

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Back in August 2015, the FM insisted she would put her “neck on the line” over the key promise.

But eight years later, the Scottish Government is still failing to close the attainment gap, with Education Secretary Shirley-Anne Somerville’s remarks earlier this year casting doubt over whether it will ever be achieved.

Analysis by the Programme for International Student Assessment (PISA), revealed that Scotland’s attainment in both maths and reading has been falling on the SNP's watch.

For reading and maths, Scotland’s score has fallen.

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Two years ago the Organisation for Economic Co-operation and Development (OECD) drew up a report on Scotland’s education system, posing key concerns about the direction of travel.

The OECD study found that Scottish Government's system was “at risk of policy and institutional overload” and had no “identified cycle of policy review” to ensure best practices.

Pressed last month, Ms Sturgeon insisted she was "proud" of her Government's education record.

Despite throwing more than £1bn at the issue, Ms Sturgeon's failed key promise to eliminate the attainment gap will always cloud her legacy on education.