For a very sporty and academic 8 year old boy, if you are going to pay, I would seek a selective, academic school with facilities, such as Newton Prep. or a normal Prep., such as Eaton House or Northwood Lodge. Broomwood would be great for an arty, creative child, as would any traditional independent school. If you were considering that bit further in Wandsworth, I would look at Prospect House or the smaller Wandsworth Prep. I think you will however find that state schools are perfectly good too and "better" than some of the private schools, especially the less academic ones. Their teachers must adhere to stringent rules set by the government and they are not run on politics or money.