Best day at the beach - ideas?

[MutteringDarkly]

Taking DC to beach soon (UK) and looking for fun ideas / activities we can do together, as they're reaching the age (9) where there is a limit to how many holes they will dig There won't be other children or adults to play with this time. We'll take a ball, and splash about plenty, but just posting here in a shameless attempt to get more ideas please.

Body board? Sand sculpture? (I have no idea how one goes about that, but sure, what’s youtube for?)

Ice cream. Is it a shell or stone or sand beach? Collecting stuff to make other stuff at home?

Sand (thankfully - all my childhood holidays were pebbly beaches).
I hadn't thought of sculptures...heading to Pinterest now!

Sandcastle with moat timed so that you can see the moat fill when the sea comes in. That has always been my kids’ favourite thing. They hate it when we arrive as the sea is going out! Can add flags and decorate with shells.
Making a sand car or spaceship to sit in, easier than it sounds
Draw around their shadow in the sand
Sand skittles - roll ball at sandcastles
Hangman in sand writing

Leave them to entertain themselves and use their imaginations?

Things we do:-

Bodyboard (Decathlon do cheap ones)
Rockpooling
Disposable bbq, sausages and buns (pack up the bbq afterwards please!)
Reading
Driftwood/seaweed self portraits

My 9yo likes kites, building increasingly intricate sand castles, body boarding, swimming, exploring rockpools with a guide to identify things and playing with those velcro ball and catcher things.

We always take the kids boules set (the plastic colourful ones). They’re good on sand and the kids like playing and I don’t mind because it doesn’t involve any running about.

These are great - sandcastle bowling likely to be v popular.

And thanks for the suggestion they can amuse themselves. I'm sure they will for some of the time, but my 9 year old on their own may run dry / need someone to play with or some help with ideas