Is marshalling a school Fun Run work?

Is volunteering for your child's school work?

A stay at home mother does not need to ponder this.

A stigmum, "technically" a stay at home mother, must for she is kept by the State and as such must answer to it (roughly every six months at the moment but the law's changing)

For the stay at home mum, is work the cooking, cleaning, shopping, admin, caring for child and children and oh how the list goes on?

For the stigmum, is work the shelf stacking or data input for a Private Company (even though she must do all the 'work' stay at home mothers do because it doesn't do itself)?

I pondered this as I marshalled the school's Fun Run, the first of its kind to encourage fitness in all pupils regardless of size and ability. The kids were amazing and got a real sense of achievement from it. I'll volunteer next year if I'm allowed to.