I think it’s good to have a few ideas on the go before acting. It’s great to involve kids in activity decisions but kids get upset/disappointed if you say something like “maybe we’ll do *this* on the holidays” and not actually do it. The weather can also impact which activities can be done.

A mixture of both. Especially days that my husband would join were planned

My kids aren’t at school yet but we try and do a lot of things while I’m on mat leave to make the most of my time at home.
We do half half as in half planned, half on a whim.
Things we plan are stuff like going to the museum, aquarium, zoo etc. as generally if you book online in advance you get a discount.
Things like going to the park, out for ice cream and to the pool or beach we just decide on the day.

It’s always good to have some craft activities ready eg paint by numbers, puzzle books, air-drying clay etc.

Some activities were planned. If I needed to book tickets for example. A lot is just spur of the moment. Eg suns out, let’s head to the beach. Bit cooler today, lets go for a bush walk etc

When my child was younger I’d look up school holiday activities run by my local council and book them in a week or two before holidays started. It was a great way to keep busy during the holidays and usually didn’t cost very much at all.

I usually did stuff on the spur of the moment. I never told the kids either, I kept it as a surprise, that way they weren’t upset if it didn’t eventuate

Some things require planning, such as events you need to buy tickets for. But most are spur of the moment. It’s the holidays, go free range

we organise a couple of outings in advance but mostly we play it by ear. We see how feral the boys are each day and plan accordingly.

Plan ahead of time and book in activities as even free activities often need to be booked ahead of time for numbers. A plan for the holidays is a good idea for everyone in the family.