Hi Wyldkat
Once we worked out the link between food and mood we got into a routine of giving him something to eat every hour or so - we didn't let him go past 2 hours without something to eat or boy did we know about it. He is much better know and eats more at meals to see him through but we still have to be on it.
Kindy thought it bizarre when we first started and we
gave them a heap of snacks and a tub of jellybeans - in case of emergency. They soon twigged after his first tantrum. We explained that if his sugar gets too low its too late and he can't eat and tantrum at the same time so pop in a jelly bean or 2, (never known to refuse them!) then once he's calmed down feed him. They pretty much learned to keep the snacks up.
Even school learned the hard way that he is unbearable if hungry and after I pointed out that he was coming home with food in his box they said well he eats soooo slowly that the bell for play goes before he's done. I had to insist that he has to eat everything before he gets to play otherwise it was compounded by him burning off the few calories he had eaten by the end of lunch and they wondered why they got nothing out of him all afternoon.
He is nearly 7 now but we still never go out without a snackbox. (oh he is celiac with several major food allergies so its not that easy to just stop and feed him when we are out, so it's a bit like taking his medical bag wherever we go we also take food).
Not sure if this helps but when he was younger we didn't worry too much about the set meal times just kept feeding him little and often - and he got a mix of good and not so good but the poor kid misses out on so much nice food we feel a treat won't harm.
