Day out/activity with 9 & 13 year old

[scaredsadandstuck]

I'd like to do something with my boys tomorrow before we get back into school routine. Any suggestions for something not mega expensive - and possible or sort at last minute - that would work for a 9 year old and a 'too cool for school' 13 year old? They've already seen the Spiderman movie and they aren't sporty. Help!

Should have said we live near to a medium sized town and countryside. We've got easy access to London so I suppose that's a possibility too but the thought doesn't fill me with joy!!

My kids are 9/15. Things they both enjoy. Bowling. Go ape. Go karts. Indoor climbing place. And specific to our location historic dockyard and Beaulieu museum.