When there are multiple parents in there with infants, younger children, older children, buggies, giant puffa coats/dryrobes swishing and taking up space, demanding to know where Elsie's cardigan is, where's Timmy's club being held, where the Head is because the class teacher looked at Dad a bit funny, I'm stuck behind a broken down bus so can you let Jamie go on with Freya's Mum please, sorry, I've lost the permission slip for the trip to the wildlife pond, my Mummy hasn't come to pick me up, can I have my medicine back, why won't you let me pick up my grandson, he knows who I am, this all the doing of my son's ex you know and my Parentpay login doesn't work, along with the delivery of 32 boxes of A4 paper, pink, light green and baby blue arriving at the same time - the school office at kicking out time is absolutely not a good place for a tired, hungry and irritable 5 year old to be for a cosy sit and story - even if they actually have any chairs in the first place.
She needs to be out, walking, eating, not thinking, not carrying a bookbag, PE kit, cardigan, coat, scarf, hat and gloves and not having further stuff going on around her and in her face/looming over her head (because almost everybody's three and a half foot and eight stone larger than her). No conversation, no questions, nothing to want to escape from.
Mine usually took one look at the crush for the front gate and pegged in exactly the opposite direction towards the field at that age, unless I was carrying food. Then, as the effect of being subjected to six and a half hours of solid auditory and visual noise with added demands upon behaviour and brain faded away, she was able to just put one foot in front of another and eat.
Similar tactics work for dogs, too. Lumps of cheese he had to snuffle from my closed hand were good at encouraging him to come back and calm down for a peaceful stroll home after a big old run & bark around and some training.