Hairspray just keep offering other stuff first, then give him the banana and yoghurt for dessert when he refuses the rest.
A lot of the activities during the half term will be aimed at school aged children, so unless there's something you specifically want to do, I would also go outside of school holidays.
Some places may still be running Halloween themed things outside of half term, eg there's a place near us that does a spooky maze for the whole month.
TBH, at that age, all you need is somewhere with a pumpkin patch for cute photos! 
It's drizzly here, definitely autumnal.
After sitting in my raised bed since the end of June having a bachelor party (all male flowers!), my squash plants have just set fruit. I'm not holding my breath they're going to ripen before the frost hits them 