Hi Aquinas,
I have not been on these boards for ages, but thought I would check in. My son is almost exactly a year older than yours. In the past year, his learning has become remarkably more independent. I have to say age 5.5 is really a pleasure. I wish I could hit the pause button for a while...
We chose to homeschool and it has worked for us so far. In your shoes, I would hire a private tutor (or nanny) whose main roles are to play and shuttle to extra curricular activities. These kids learn so fast, you can cover material when you are home from work.
My second choice would be the play based kindergarten. I think a lot of damage can be done by a bad academic fit and PG kids have long memories...
I would be hesitant to put a 5 year old boy with 8+ year old boys regularly without significant scaffolding, because you can run into some pretty negative bullying situations (or at least power plays). You need a very special group of kids to avoid that kind of dynamic -- particularly if the 5 year old boy is viewed as smarter than the 8 year olds.
