Further corroboration appeared this week of the fact that ministers and Department for Education spokespeople have been fibbing to us all this time. The Institute for Fiscal Studies (IFS) declared that UK schools have experienced such swingeing cuts for a decade that it will take £4.9 billion of new money to get them back to 2009 funding levels and protect them until 2023.

But we already knew that: the Association of School and College Leaders (ASCL) reckoned earlier this year that the constant squeeze on schools left them currently £3.4 billion short; project the requirement forward and the ASCL and IFS figures match closely.

These calculations reappeared as a result of the Conservative leadership election. Tory poster boy Boris Johnson was airily bandying around his usual mix of empty promises and inaccurate criticism. He pledged to end the “postcode lottery on school funding” which, he said, sees per-pupil funding vary between £4,200 and £6,800. He was out of date: those geographical vagaries largely ended with the common funding formula in April 2018. Meanwhile, Boris’ guarantee of £5,000 for every school pupil in the UK made a slick soundbite - but represented only an additional £200 per student, a paltry boost to the starved system of £40-50 million overall.  

That’s Boris for you: bluff, hearty, firing from the hip and so essentially misleading that no one in their right mind takes his blandishments seriously (apart from the Boris-supporting Tory right, which voluntarily surrendered its right mind long ago). Besides, he’s not the only would-be PM throwing largesse in the direction of education. Michael Gove, himself a former education secretary, pledged a cool £1 billion to education before he was ejected from the race.

That was a more serious figure, but it’s not enough. The shortfall identified by ASCL is more than three times Mr Gove’s offer, or a fifth of what’s needed to plug the gap for the future. Better than nothing? Or yet another insult, further salt rubbed into the very significant wounds suffered by schools and teachers and by the children they struggle to serve?

At least those two are offering more cash, you might argue, even if it’s not enough. During Tuesday night’s excruciating televised debate between the candidates, foreign secretary Jeremy Hunt slipped in the Daily Mail-style accusation that a quarter of children leaving primary school can’t read.

His assertion was unfounded, a lie no more forgiveable than ministers’ oft-repeated assurances, when tackled on funding, that government is putting record sums into education: that monstrous untruth has been called out more than once by government’s own auditors.

Does it matter anymore? After all, we’ve become accustomed to living with exaggeration, double-counting and obfuscation from the political classes.

I think it still matters. The thank-you letter to teachers from education secretary Damian Hinds on Wednesday was an illustration of the way such evasion has become endemic. The letter’s tone was warm and appreciative, but it lacked any honesty about the problems confronting them every day. Mr Hinds deplored the fact that, according to OECD’s latest Talis (Teaching and Learning International Survey) report, UK teachers are working longer hours than most in the world; he sympathised with their frustration that so much work is not directly related to teaching, and applauded schools and school leaders who are trying to reduce it.

But he failed to acknowledge that his own accountability system is most to blame. Relentless pressure to perform, convoluted machinery to prove that they’re performing, and insufficient resource to support their efforts: these are driving teachers out of the profession.

But still Mr Hinds avoids all mention of funding and offers no other relief on the issues making teachers’ lives so hard, beyond the customary politician’s assurance that technology will help - er, somehow.

So now I’ll add my own thank you. Thank you, teachers, for doing all that incredible work for the nation’s children: for remaining (generally) good humoured and always ready to help the kids who need you; and for putting up with the empty promises and half-truths that, sadly, are all you get from government. 

You deserve so much better.

Dr Bernard Trafford is a writer, educationalist, musician and former independent school headteacher. He tweets @bernardtrafford