WHAT I want to know, as yet another Year 3 checks my seat belt, is what I'm here on this coach for. To keep them safe, to help them learn, or just to carry their stuff? Am I surrogate mum, teacher or yak?
Harry drops his bottle of sunscreen (family size) into my bag, while Izzy complains about a wrist she feels may be broken.
On the last trip, to one of those wildfowl parks, Harry asked me to look after his present to his mum: a 25p bag of birdseed.
"Will she like that, do you think?" I asked.
"Of course she will," he said. "She always likes my presents."
Today it's the seaside and when we get there the glare is terrific. In spite of no-touch directives I slather sunscreen on young faces, necks and calves.
Izzy asks if I can make a sling from her sweatshirt, while Olivia stares at an addict shaking in a sun shelter, and while Toby stares at two bronzed young men holding hands. Well, this is Brighton.
"After your ice creams you can make sketches of the West Pier."
Toby sketches the memorial to Boer war dead instead.
"What was that war about, then, Mrs Parkin?" This is even worse than the trip when I found myself extemporising on the D-day landings. Luckily Olivia gets a splinter.
George and Toby start moaning that they have no money left and Harry shoves his unwanted rainwear into my bag.
"Look, here's an information board about how the pier is to be restored." But I can hear the first few notes of "She'll be coming round the mountain...".
George and Toby are sitting cross-legged on the prom, playing a recorder duet with Toby's sunhat at their feet. He has primed it with 3p.
"You can't do that! Get up!" "But we're really hungry and we've got no money," says Toby, as George segues into a solo of "What shall we do with the drunken sailor?" I buy them chips all round. Harry saves four for his mum. In my bag, of course. And there's my answer. Those who can, teach. The rest of us are yaks.
Jill Parkin is a parent