When is discrimination not discrimination? When everyone agrees to it. Not classic Christmas cracker material, I grant you, but sexism is a sterile soil for gags. Are we encouraging it in schools?
Most would howl at the charge, but if discrimination means treating one group differently from another on the grounds of an arbitrary distinction then we certainly often do: toilets, uniforms, even some classes - such as PE - that routinely segregate. If we replaced gender with, say, ethnicity in those distinctions then the streets of Hackney and Cumbernauld would echo with demands to let freedom ring. Instead, people write occasional polite letters to newspapers.
Why does gender enjoy such ideological ring fencing? Has the regime become so pervasive that it is invisible? Maybe. Maybe not. Rosa Parks emblematically demonstrated that the policy of "separate but equal" was anything but equal, because the separation of ethnicities created a partition that reinforced the existing hierarchy. Martin Luther King reminded everyone that a partition unsupported by common consent is a prison wall, not a picket fence.
And that's where we enter conceptual territories that defy easy categorisation. Some of the segregation in schools enjoys support from broad constituencies that straddle the X and Y chromosomes. Toilets, for one. It's hard to form a picket line in front of them when people are queuing up to micturate, gladly and happily. False consciousness? Slave mentality? That's a hard charge to lay at the cubicles of men and women who are largely happy with the arrangement.
Of course, life doesn't always present such simplistic binary options of identity; look at cases of gender dysphoria or subtle variations of sexual and physical identity. On the other hand, we tinker with the expectations of the majority at our peril. I remember the battles that would break out as transsexuals, transvestites, gay and straight humans disputed the rights of toilet occupation in the clubs I used to run. Solomon himself would have struggled to discern the victim from victimised, oppressed from oppressor.
One alternative is favoured by a growing number of schools: unisex cubicles. Some even go further and merge staff and student toilets. The vim of the architects of such enterprises must only be matched by their antagonists' venom, but some schools do report success.
There's nothing particularly logical about segregated toilets, but then there's nothing logical about why you might prefer Schubert to Slipknot. The argument for and against toilet segregation becomes one of preference rather than social justice, like whether to leave the lavatory seat up or down after use. That said, proponents of the unisex loo do tend to overlook the utility of the urinal in their analysis.
So until someone discovers a way to re-engineer human plumbing, let alone the secret gardens of preferences, it seems that the walls will stay up. And there will always be at least one room in the school where half the teachers can't get you.
Tom Bennett teaches at the Jo Richardson Community School in Essex and is director of the ResearchED conference