A jumbo five-sided dice is due to land at the Schools Week towers this week.

It is smooth, blue, an odd triangular shape, with faces only showing numbers 1 through 5.

It’s my “grammar school gamble” dice. The game is easy to play.

Imagine you are the parent of a child in the last year of primary school who is receiving free school meals. You don’t have any good idea if your child is smart, or not. You think they probably are, but maybe the teachers are being polite?

You are given the grammar school dice. If you roll it, and get a 1, then your child will get a better school than they are guaranteed right now. But, get a 2, 3, 4, or 5, and they will attend a much worse one.

Do you do it? Do you roll the dice? Or do you stick with the status quo?

Every politician in the land ought to be asked that question before giving their public support to proposals to return grammar schools.

If they wouldn’t roll it, then there’s no reason to make anyone else roll it either.

To her credit Nicky Morgan has at last shown some gumption and said she wouldn’t roll. Michael Gove has done the same.

To his credit, Heath Monk, executive director at the King Edwards Grammar Foundation, has written for our paper this week, explaining why he thinks the dice odds can be shifted.

But, as Dan Moynihan, chief executive of the Harris Federation – which has turned around dozens of comprehensive schools – says, there simply isn’t any proof these tweaks will change the odds.

school leaders clamber over each other, grabbing the smartest children and shunning the “unwanted” – like a scene from a dystopian future

Moynihan also admits that if schools are allowed to become selective at 11, then he may well feel forced to take part.

A desolate arms race in which school leaders clamber over each other, grabbing the smartest children and shunning the “unwanted” is like a scene from a dystopian future. One that is all too easy to imagine, sadly.

Groups are already organising against the plan. The Fair Education Alliance has created a petition and a planned rally. Conservative MPs are co-creating arguments with Labour MPs. Teach First has taken the unusual step of coming out against government policy and is asking the 10,000 ambassadors from its programme what actions they want to see next.

It’s a smash on the nose for a new prime minister who seemed to think she could throw out a consultation labelled “schools that work for everyone” but only mention religious and high-ability pupils.

But it’s also a hell of a lot of energy for something that is a long way from being a policy and at a time when the school community is already facing a series of funding, staffing and curriculum issues.

The worry is that this is a “dead cat” – that is, a policy designed to take everyone’s eyes away from real issues. (So named after Lynton Crosby, the election strategist, who once said that if you are losing an argument then you should throw a dead cat on the table so that everyone starts talking about the cat and stops having a go at you).

We’ve given a lot of coverage to grammars this week. In part because it’s a live issue, but also because we know so many people are against, with the ASCL-led survey this week showing 80 per cent of teachers against the policy.

But we also won’t be taking our eyes off other stories too.

Education shouldn’t be a gamble and too many other schools issues need resolving before starting to make the grammar school gamble fairer or wider.

Hence, it is right to put energy into opposing this. But let us not use it all up when there are more urgent battles.

Should you need a quick way of convincing anyone against grammars in the meantime, however, I have a five-sided dice you can borrow.