That '4th grade level' is as much a testiment to dumbed down standards as it is to your kid's brains. Homeschool, it is cheaper than private school.
He likes the school he goes to. The teacher actually taught the kids how to sing "God Bless the USA", which is verboten to P.C. police in two different ways. I was amazed when he told me that. But they do not have the resources to keep up with his advanced reading, and the magnet school does and seperates kids by ability and interest. We did homeschool him in a way. He never attended pre-school of any kind and he learned to read before age 3. But that isn't possible for us now as he has a a sister and my wife and I are in business together. Private school is completely out. We cannot afford it.