I call up some teachers and parents and ask them if they’ve seen the new report on the Higher results. Yes, they’ve seen it, and no, they’re not surprised. They tell me about class sizes, and staff shortages, and the effect it’s all having on the kids.

But they also tell me something interesting about how it might impact on the Scottish elections. My advice to the Government would be: sit up and pay attention because this is definitely going to affect you.

First, a recap of what the report said. The number of pupils achieving passes in the core Higher subjects dropped significantly in 2019. Maths: down 2.1 per cent. English: down 5.5%. And history: down 10%. There were some subjects that showed an improvement – PE and biology for example – but overall the picture was grim. And it didn’t help that the Government tried to sneak the report out last thing at night when they thought journalists wouldn’t be looking. Wrong. It just made the whole thing look worse.

The terrible Higher results are also, clearly, a symptom of several deeper problems in Scottish education, but two in particular came up in my conversations with the teachers and parents. First, the effect that large, mixed-ability classes is having on pupils, and second, the effect that workload and staffing is having on teachers. Parents and teachers are worried, and stressed, and have been for years.

But let me tell you about one teacher and one parent in particular because they’re the ones who know what’s happening on the ground. The teacher has more than 20 years of experience in English and works at a city comprehensive with a mixed intake; the parent is a mother of two kids at secondary who are also at a mixed-intake school. Both the teacher and the parent have voted SNP in the past (in the parent’s case for 25 years); they also support independence. This is significant because what they, and others like them, do next is going to affect the Scottish elections in 2021.

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So here’s what the parent told me. The Curriculum for Excellence isn’t working. Class sizes are too big. The wide range of abilities in classrooms is badly affecting the brightest kids who aren’t getting pushed to their full potential, with the result that everyone gets a middling mark and results start to suffer. She also said teachers were too aware of the league tables and held some pupils back from National 5 to make the results look better. And she said she felt forced to get tutors for her boys even though money is tight. The situation is bad, she said, really bad.

HeraldScotland:

Now here’s what the teacher told me. He too said that the Curriculum for Excellence isn’t working. He also said pupils are suffering because there are so many kids with additional support needs in mainstream classes with next to no support. Then there’s staffing. Teachers are sourced from overseas to fill the gaps, but when they arrive, the reality quickly becomes apparent and they leave again, so more teachers are sourced from overseas. The phrase the teacher used to describe the education situation in Scotland was “freefall”.

The consequences of everything they said are clear. If you have some pupils whose potential isn’t being fully realised, and you have some parents employing tutors, the gap between the better-off and less-well-off pupils is going to get worse. In fact, it’s already happening. In the words of one parent I spoke to “those who can’t afford tutors are seriously stuffed” and the government report admits it too: lower-attaining pupils, it says, are not improving at the same rate as higher-attaining pupils. The effect of parental income was also obvious in The Herald’s story at the weekend about the falling number of pupils taking music tuition because some councils have introduced fees.

The potential political consequences are also interesting. Some of the people I spoke to are not SNP supporters, but the mother and teacher I’ve quoted are. They also both voted Yes in 2014, but how they’ll vote in the 2021 Scottish Parliament election is up for grabs. The teacher tells me he spoiled his ballot in last December’s General Election and there’s no way he would vote SNP next year. The parent did vote SNP in December (just, because of Brexit) but said she won’t vote SNP again until the situation in schools improves. She may vote Green, she hasn’t decided.

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What this means, if replicated more widely, is the SNP is unlikely to advance in 2021 and the majority they need for a second referendum is at risk. Some disgruntled SNP voters will switch to the Greens, like the mother of two says she may do, and this means there could still be a combined Green/SNP majority. But with the education situation so bad, and with so many parents and teachers unhappy, there’s also a chance that enough people will feel unable to vote SNP next time that they will narrowly lose their majority, even with Green support.

The issue of independence will, obviously, keep some people in the SNP fold, but increasingly I think some voters are prepared to separate out support for independence and support for the SNP. The teacher and parent I spoke to would still vote Yes to independence if or when they get the chance – their support for that hasn’t wavered one bit – but their disgust and disillusionment with the SNP over education means they are prepared, for the first time, to vote against them at a General Election. They know that failing to support the SNP puts a second referendum at risk but they are prepared to do it anyway and leave the issue of independence for another day.

This is perhaps the lesson that the SNP needs to take away from all of this. There are some SNP supporters who think the party is immune from the usual political consequences of doing a bad job on schools or hospitals, and to some extent, for now, it is. I also think scandals like the Derek Mackay affair are not going to have much effect.

But on policy and performance, the cracks are there. They’re in the overcrowded schoolrooms, and in the living rooms where children are getting extra tuition, and in the staffrooms where teachers are talking about their daily struggles. These cracks could grow, or they could heal. But whatever happens, the crisis in education could be the issue that narrowly decides next year’s election.