S.C.
I have a friend who has 2 children attending Walnut Creek Private school and they love it! I haven't heard anything negative about it!
Also, I have heard good things about St. John's too.
My son goes to Treehouse Academy in Arlington on Matlock and Turner Warnell. We love it there! He has learned so much since we moved him there. They have Pre-K there also. It is very affordable, too! My son really enjoys going there and never hates to be left there, which is such a relief and comfort as a parent. Everyone in the facility knows his name and knows who I am when I enter the building. I feel very safe there and I am positive he is learning and building good relationships there.
Let me know if you want anymore information.
Good Luck!