There were definitely some trans pressure groups going into schools. Unless ours was just unlucky. Couple of years back, possibly GIRES. But one 'gender' type group were due to be doing a session with the kids. My daughter at the time was 5. It was around the same time I was waking up to all the stereotypical bollocks after previously being very 'be kiiiind'
The parents I knew, I told what this group were and the kinds of things they 'teach'. Those parents told others, and long story short, it turned out almost all parents were going to pull their kids that day, so the 'lesson' was canceled completely, and no mention of anything similar since, thank god.
My daughter has always been into a lot of 'masculine' stuff, shes also suspected to be autistic, so she had quite a large chance of being sucked in by people who basically convince her shes actually a boy 
Its just a flat out lie to say lobby groups have not been into schools, had an impact, produced 'training materials' and such..but it seems everything to do with such groups is furiously being scrubbed from memory/existence now. Mermaids claiming that they ever said stereotypes meant anything is just bloody hilarious.