Everyone views inbreaths and outbreaths differently.
The important thing is to go between them in a rhythmical sequence so the little children aren’t caught holding their breath.
These are all metaphors, of course, but excellent ones for understanding children and what causes overwhelm or meltdown, and also joy or exuberance. For me, freeplay outdoors is the very heart of an outbreath. The children can move freely! They don’t have adult intervention or input. The adult merely prepares the safe space for the children to play in, and stays nearby to help with budding social skills. It can be an outbreath for the adult as well if they want to work outdoors on projects. Within this larger outbreath can be micro-inbreaths. A child resting in a teacher’s lap. A birdie-nibble (snack) at the table. A trip to the bathroom with one-on-one help from the teacher. Sitting on the still swing or step, daydreaming, looking out at the day.