So religion is "inappropriate" in the maths class. Though not, apparently, role playing: "Look, he thinks he's Napoleon. No, don't laugh - that would be bullying - let's all call him Emperor (Empereur to you posh ones)."
Of course, being forced to participate in this particular delusion could turn out to be trickier than you think. How many genders identities are there today? (The LGBTQWERTY acronym has wrapped round several time by now, hasn't it? And new "identities" are being invented all the time in Gender Studies departments everywhere.) Each of these has, or will have its own preferred pronouns, the refusal to use which can and will be viewed as "disrespect" or worse. (As an aside I'm not sure that all languages are equally up to speed on this issue. I've been following the Jordan Peterson affair in Canada and I don't think French can accommodate the full gender identity spectrum, leaving the millions of trans-gendered-two-spirited-neutro Quebecois robbed of their dignity.). The trickiness I see is this, we've got to allow for gender-fluidity. What happens when Pupil A is a "he" today", but a "her" tomorrow? How are we to keep up with this? One solution, I suppose, is the gender identity bracelet. Here's an example:
https://www.etsy.com/listing/192328665/gender-identity-pride-bracelet
Although in this example there's only three of them I can't tell which is which. This is going to need lots of teacher training by lots of teacher trainers, and lots of monitoring and enforcing by the the kind of people who like monitoring and enforcing.