We're 2+2 (10 & 4) and we often go to Goosewood (Sutton-on-the-forest).Its about 10 mins drive from Clifton Moor on the York ring road. No pool on site but there is a "Splash world" type place not too far. Also cinema, 10 pin bowling and supermarket, etc. at Clifton Moor. Additionally the site is quite close to the Rawcliffe Bar park and ride centre, which is excellent for access to York itself. The site is very private and has excellent amenities. There is a large adventure type play area for children and a large fishing lake. The site is ran by 'Best of British', so of a good standard.
P.S. The pictures you find of the site do not, in my opinion, do it justice. Simon