My wife and I just decided to teach our Kindergarten-age daughter at home. It was a tough decision, as there is a nice public elementary school less than a mile away, and her same-age cousins are going to a small Christian school across town. For us:
-The Christian school is too far away and too expensive
-The public elementary school would require us to buy a 2nd car. I bike to work down to -20F, but we have many days between -20 and -40F here in Interior Alaska, so both my wife and I would need a car some days. Bus service is not available so close to the school, but is too far to walk with an infant in tow at sub-arctic temps. And I'm too much of a weenie to reliably bike my 4 miles to work below -20F.
-In our area, you are reimbursed (by the public school system) $50/month for internet plus up to $2,000 per year for curriculum if you home school. Scholastic curriculum for children is nearly free, so that means you can actually spend money on things that develop their other talents, like music, art, skiing, etc., with no out-of-pocket cost. Incredible. One final thing we found is that our daughter is already well socialized through extended family and church, and we're not too concerned that she will be a recluse. As one woman said to us: "Yes, socialization is important. But socialization is not better just because it's at school. After all, they are learning social skills from other five year olds there. I think you can do at least as well."