JOHN Swinney will address thousands of teachers at a major education conference today ahead of a key debate in Holyrood on whether children in primary one should do literacy and numeracy assessments.

The Education Secretary faces a knife-edge parliamentary vote after Labour, the Greens and the Lib Dems signalled they will back a Tory motion calling for the tests to be scrapped.

READ MORE: How do the controversial P1 online assessments work?

Ahead of this afternoon’s debate Swinney will speak to participants at the Scottish Learning Festival in Glasgow where he is expected to argue for the merits of the policy which has divided expert opinion. His officials yesterday demonstrating the tests to politicians and journalists in bid to ensure an “accurate and informed debate” and help explain the thinking behind them.

READ MORE: P1 children should be learning through play, not computers

The Tories – who backed P1 assessments in their 2016 election manifesto – will lead the Scottish Parliament debate – a backtracking which has led to accusations by ministers that the party is exploiting “the issue for political gain”.

Nicola Sturgeon last week criticised the Scottish Tory leader Ruth Davidson for dropping her 2016 manifesto pledge supporting the assessments.

“We welcome the Scottish Government’s recent decision to reintroduce national testing in primary schools. It is an admission the current system has not been good enough in creating clear, consistent and transparent data on the state of our schools,” the Tories’ document said.

“This problem has been identified by numerous reports examining Scottish education. We believe the Scottish Government needs to be far bolder in measuring progress in our education system.

“Only by measuring properly can we assess whether schools are meeting the gold standard parents want. The Scottish Government should commit to re-entering Scotland into all the main international education comparison tests: PISA, PIRLS and TIMSS and design the new standardised tests at P1, P4 and P7 to fit into these international methodologies.”

Today’s vote will not be binding on the Scottish Government – and Swinney, who also holds the position of Deputy First Minister, has continued to stress the “merits of standardised assessments and the benefits they can bring”.

Swinney yesterday argued the tests are “a valuable tool for teachers to identify the next steps in a child’s learning”, adding the “additional information they provide is particularly useful in the early years if we are to continue to close the attainment gap”.

The Education Secretary continued: “They are designed to be delivered as part of everyday learning and teaching, they are not high stakes and there is no pass or fail.”

Tory education spokeswoman Liz Smith said standardised tests could have a “key role” in improving standards in Scotland’s schools – but not in P1.

She said: “We will continue to support the introduction of tests in P4, P7 and S3 and will back the Scottish Government in its efforts to do so.

“But the SNP needs to rethink its plans for those tests to be introduced in P1 and call an immediate halt.

“Parents and teachers are all raising concerns about the way these are being introduced. And the truth is it would be irresponsible not to listen to them.”

The Conservative added: “This debate is a chance for the Scottish Parliament to have its say on this matter and it is time the SNP’s bluster on this important issue stops.”

Labour meanwhile said the tests were “completely discredited” as it branded the Swinney’s demonstration of them as a “desperate stunt”.

Education spokesman Iain Gray hit out, saying: “The idea that civil servants performing the tests to MSPs is in any way equivalent to the pressure felt by a four-year-old sitting them is utter nonsense.

“The Scottish Parliament has the opportunity to vote to scrap these tests for primary one children. If the SNP government were to ignore such a vote it would simply underline how out of touch ministers are on education.”

Green MSP Ross Greer, the party’s education spokesman said: “John Swinney had one last roll of the dice, attempting to convince journalists and MSPs that all is well with standardised testing through last minute demonstrations.

“Instead, he should have listened to the teachers, pupils, parents and education experts who have demonstrated for months now what the Greens and others have said all along, that these tests do more harm than good and they should be scrapped. That’s what the Green MSPs will be voting for today.”

The Lib Dems’ Tavish Scott said that “when Parliament votes with teachers and parents to halt national tests for five-year-olds, the government must accept that view”.

Referring to the Tories’ previous support, the SNP’s Gordon MacDonald, said Davidson’s party was “grandstanding”. “The Tories are guilty of grandstanding, preying on the anxieties of parents and blatant political opportunism. And they’re prepared to do so at the expense of kids’ education - it’s an utter disgrace,” he said.

“The Tories are seeking to create monster out of a serious challenge we should all unite behind - driving up standards in our schools. To do that, we need data from P1 to ensure we’re making progress.”