To ask best way to entertain 7-13 year olds

[Snorkers]

I am a (geographically distant) neice to 4 lovely kids who are coming to stay for 3 days over a Bank Holiday weekend next year to give their mum and dad a much needed break. Bil has been v ill but now on the mend.
I don't have my own kids but I really want them to have a great time and am trying to get an outline plan in place soon in case I need to book tickets in advance.
They are all quite into science stuff except one, who is mad on trains.
Aibu to ask what are your best days out or activities for kids this age?
I'm not rich but don't mind saving a few hundred quid for the weekend.
What on earth is popular with kids this sort of age now??
Thank you!

Treasure hunts, assault course in the garden, rock painting to plant around the town, see web page Notts Rocks. Craft activities, Local parks may have events over the weekend. A good age to take out to places by bus or train

You will probably have to factor in a bit of screen time

Cinema and board games i would go for. Baking might be good too or something like letting tjem make their own pizzas.

Where in the country are you?

Where do you live (roughly!). If it's London or near London, you'll have no problem.
They will also no doubt bring their phones/tablets with them!

If you can get a deal (Groupon, Tesco vouchers etc) on any of the following, they're very popular with the 7-13s I know:
Trampolining
Climbing wall
Swimming

Escape rooms
Geo caching (that one's free)
Rollerskating
Go Ape type activities
If you're anywhere near London, the science museum is great. There's also We the Curious in Bristol and a similar one in Newcastle (can't remember the name, though).

Movie evening - make your own popcorn
Mine love getting together with cousins to make a film on a phone or ipad - they can spend hours on script, costumes, scenery etc!

Trampoline park if you have one locally
Swimming if you have a fun pool with slides etc locally and they are all able to swim
Science museum if you’re near one
Bowling
Ice skating if you’re near a rink
Cinema but it can be hard finding a film suitable for that age spread
Open top bus tour of your nearest city

My kids and their cousins (similar ages - youngest 7, eldest 14) love trampolining, swimming, cinema, climbing (indoor clip n climb type thing), crazy golf
The older ones will def want some downtime to keep up with their friends on social media too!

Amazing thanks.
I am South east, but I don't want to take them to London as I think my head will explode. Driveable is good, and thanks for the ideas for at home too.

Geocaching??
I've literally never heard of it!

Can you hint at where in the south east? Nearest major town for example? These things tend to be local. I'm south east nr Reading and Basingstoke - any use? If so will compile a list 😁

Gosh thanks. Near mid Sussex. Thanks!

You sound so lovely OP to be giving this visit so much thought. Geocaching is great fun. Mine range in age from 9 - 20 they all love scavenger hunts in local woods, trampolining , picnics, trips to the beach, bowling, laser quest and the cinema, although last one always causes a bit of debate. Making pizzas great too. I tend to have a fair weather plan, which is cheaper and then a wet weather contingency which costs a lot more. Keep costs down by taking drinks and snacks with you.

There are some good Forestry Commission places near there - you pay for parking, there are free playgrounds, fairly short trails with things to climb / balance on / swing on and also bikes to hire, sometimes Go Ape (though the latter get expensive).

You should also check about car seats, if you’re planning to drive them. My 10yo still needs a booster, and my 7yo is still in a big HBB. Fitting three of those across the backseat is often impossible.

Train to Brighton - there's loads to do there. Arundel Castle and Lewes Castle are also great.

Bluebell railway!

Tilgate Park is also lovely, and has a small zoo if any of them would like that?

Mid Sussex (according to the map) is a quite a large area. However, you might be quite close to Brighton (great day out, weather permitting), or Arundel Castle is brilliant - and often have special activities during Bank Holidays and school holidays.
The British Wildlife Centre in Lingfield is well worth a visit - you get to go in an enclosure with the red squirrels.

The open air museum just outside Chichester sometimes has rustic craft type weekends - think candle making etc - which might be a bit different. Also worth keeping an eye on the Festival theatre to see if they have anything interesting on. Think that there is also a narrow boat trip in the south of the city.

Amberley Museum is also a good day out (somewhere between Chichester, Horsham area).

Herstmonceux? Great science place