The netherlands has lots to offer:
We've really enjoyed Duinrell / Eftelling / Bekse Bergen
We had a great week in the summer with cheap flights TO Hamburg and HOME from Copenhagen....
Used public transport and a gorgous tourist boat trip, with a 1 way ticket to see lots of places via Sweden. It was really cheap and we had a few nights in the very nice Tivoli Hotel, after nights in a german premier inn (Far better than any english one ive ever stayed in) and a night on the ferry between germany and sweden.
We like a nice "hot all inclusive holiday" and we love swimming and snorkelling.... nice hotel where you can snorkle straight off the hotels beach..... one afternoon according to my fitbit we all swam over a mile..... then some nice boat trips including swimming from the boat. Then a water park for some fun slides and lazy rivering, and our own swim-up pool is lovely. (Blue lagoon Village, Kos)
We also love a cruise. Great to explore a new place each day, have really nice food together in the evening and great entertainment, then wake up in another city.... on sea days my children enjoy the kids clubs, and we enjoy relaxing with a book, or a sit in the hot tub,
We've enjoyed Disneyland Paris, by train. And all the UK themeparks.
We loved Lapland (did it DIY) and we would defintely go back for the magical winter activites on offer (not santa anymore)
Lake Garda has lots to offer, we did Venice (did a gondala) and Verona, Gardaland, Hired a boat on lake garda, went up Mount baldo
Manor house hotel in Devon is also brilliant. cheap and cheerful but really good family fun
Cornwall and and isle of wight have lots to offer including amazing beaches if the weather is kind. (we did those when they were slightly younger (during covid) but there would be plenty for them to enjoy now they are older too)
This year we have planned
a cruise
a hot last minute holiday once their school breaks up. (there were amazing last minute deals last year; hoping for the same)
A trip around Italy.... Naples / Rome / Florence / Pisa traveling around by train.
They are also going for to switzerland for a week of adventure holiday in the alps with scouts.
They will be going Skiing with school in February
We have Florida (not necessarily Disney), California, and Australia on our bucket, lets try to do soon-ish list.
My children are 11 and 13