Having said that, at some point they will say "I'm bored", and turn to you for help, so have some fail-safe activities ready to distract them with.
These don't have to be hi-tech things; reading them a story usually works, as does fruit-picking (we're past the strawberry season but we'll be into blackberries soon), they love that. Visiting anywhere with a maze is really good, and the more complicated the better, although you have to be prepared for the fact that somebody always wants to go to the toilet when they get to the middle. If you've got a garden then getting the paddling pool out requires relatively little of you as a parent, and always goes down a treat, but do be prepared to see your garden transformed into a swamp. Remember that your kids need a rest just as much as you do - arrange great days out for all of you but be relaxed enough to also let them do their own thing. None of this, however, will prevent you from becoming frazzled at some point - accept it, it's inevitable!
Steve Hocking is a father of three and editor of `Blue Peter' (www.bbc.co.uk/ BluePeter)