There are two competing narratives here, both asserted, neither especially well evidenced.
Radical Fem: sex merely confers physical characteristics and has zero influence over brain functions, emotions, preferences etc. This is normally ‘evidenced’ by the poster having preferred Lego to dolls and maths to cookery.
Trans: All sexual characteristics are brain based and the physical/hormonal system is secondary and accidental. Again this tends to be evidenced by personal anecdote.
Neither narratives are useful to anyone where they stop research and intelligent discussion.
Schools try to use evidence in making policy but, because of both agendae, there is precious little available.