You're playing computer games while your kids play in a pool? Strikes me as odd. Mind you, I have no children of my own, but thinking back to my childhood...well, there were no smartphones and notebooks around, back then, but still.
Anyways, you could always try sitting under a large parasol, wearing a wide-brimmed hat, and possible putting your notebook inside a cardboard box. Mix and match those methods to best suit your situation.