We made the decision to keep our daughters out of GRPS, for various reasons, and did get our oldest into the Kindergarten program at Walker Charter Academy. We LOVE it. I can't say enough about the program (and we're only 6 weeks into the school year). Our daughter is still 4, so being a young student we were offered and accepted some additional one on one help in math and reading - just to give her that boost. We also like that they do a Moral Focus program, which focuses on a new moral (based on the Greek Cardinal Virtues) each month.
The word of caution with Walker - every year they receive more applications than they have seats in the Kindergarten program. When that happens it goes into a lottery process. I would recommend putting in your application at both schools (Walker is accepting them now and will stop the end of February) and then you can make your final decision later.
Orchard Hill and Appletree Christian Learning Centers both provide transportation. For my two girls (3 and almost 5) day care was going to run around $850 a month at Orchard Hill and $1,000 a month at Appletree. Orchard Hill you pay by the month with the first month do when they start, Appletree requires a two week deposit.