Zia�s mom,
Almost five years and starting 2nd grade is defiantly a hard sell.
What does your son�s pre-school teacher think would be an appropriate placement? IF, his past teacher supports the radical acceleration, you might ask for a recommendation.
Is he offered 1st grade placement at the private gifted school that you mentioned earlier?
Are there criteria for admittance that ensure the other children are also some level of gifted? If so, I would imagine the first grade curriculum is already minimally at a 2nd grade level. Will they offer subject acceleration in addition to gifted 1st grade placement?
As others have stated, given his age, and required skills such as handwriting, you may wish to proceed in increments. I would definitely suggest the next skip occur before 5th grade if possible.