My DS4 is going to do a second year of play-based half-day, 2-day-a-week preschool in the fall. His preschool teacher really gets him and his giftedness (she was the first outside person who told us that he would need acceleration some day). An additional benefit to this preschool was the fact that I get a break! (Sometimes it's a brain drain to have a kid who is constantly on.)
We started wondering that maybe DS was more than a little smart when he seemed to teach himself to read around 3. We did have him tested with SB-V when he turned 4, because we wondered about early kindergarten and we had to prove IQ>130 and get the ball rolling in the spring if he was going to go 2008. Because DS turned out to be very HG, we're glad we got testing before school started. He will always require some sort of accommodations at school (subject or grade acceleration, etc), so we took the evaluator's advice to let him play another year instead of early k. We probably will end up doing some homeschooling at some point, but that was not even on the radar until we got his evaluation. In fact, I had pretty negative views about homeschoolers (sorry - i thought they were all just on the religious extremes). But as for you, if you expect to homeschool anyway, maybe you won't need to spend the money for testing unless you need it for some particular program or reason.
For now, we encourage whatever DS4 is into at home, and it seems he just learns stuff through osmosis. I concur with the others about following your child's lead, and do other fun stuff like zoos and science museums, etc.
