I'm trying to get a sense of if this is the way we want to go next year? DS6 is MG, maybe HG (no testing but my estimate) and having a bad kindergarten year. I fear he's learning school is just for behaving well and not for learning. I had thought I was choosing a school that would differentiate but so far that isn't happening much, and he's working well below his ability. I'm looking into options next year and one school I looked at will do pull out programs from the beginning, the other doesn't start until third grade. My question is how does that help in the classroom? If all he gets is the extra hour of enrichment a week how will that translate to learning at a faster pace that he needs?

For us enrichment hasn't helped at all. This year it's during the time that the rest of the kids in his class do art so it's hard to even get him excited about it. They're mostly doing arts and crafts and reading books and occasionally doing brain teasers.

I don't find that my son's enrichment contributes anything to his academics.

I am afraid we have the same experience as Jamie. The pull out is focused more on enrichment (puzzles, sudoku, reading advanced books; it is not enough in our DS's case) vs. academics (introducing to new and more advanced concepts).
I also volunteered numerous hours in K, and it just seemed to me that the main focus is behavior vs. learning. That is one of the reason why we have opted for grade acceleration.

I don't think that a pull-out program will help much. My DD gets pulled out once a week for an hour and she really likes it. They do fun things like pentominoes and brainstorming, and they maybe get a chance to think more deeply for an hour, and it may even touch on things like math and reading. But it's an hour out of 32 hours a week of school, so it doesn't help with academics acceleration AT ALL. In fact, in DD's case, they get pulled out during math and are still required to do the work they miss, but on their own.

I was in a pull-out program when I was a kid, and I believe it was three times a week for a couple hours each time, and it still didn't help accelerate my work in class at all. Again, we did fun things like make up recipes and participate in Odyssey of the Mind, which have their value. But it did not help me in the classroom.

IMO, a much more effective strategy for kids working ahead of grade level is to actually teach them beyond their grade level (sounds obvious!) via subject or grade accelerations.

I wanted to add that I was also in a pull out program growing up. 4-8 grade we got to go one full day a week and we did fun stuff like dissecting animals and art and computers but nothing that really helped me academically. It was fun though and I (unlike my son:) ) loved going. Depending on my regular teacher I sometimes had to make up the work and sometimes I didn't.

I was also in a pull-out program as a kid, starting in grade 2, and although it gave me all my best memories of school (great field trips, interesting experiments, fun dramas), it did nothing to address the fact that I wasn't challenged in the regular classroom. It was more like a fun club or extra-curricular activity that I got to participate in a couple of times a week.

This is what I was afraid of and what I suspected.

My ideal school would ability group by subject but so far I'm not finding that. I thought I had but so far I haven't. I have an email in to another school and my fingers are crossed that I'll hear what I'm hoping for.

The gifted pullout is only part of the Educational Plan (EP). The regular classroom must meet the needs of the student too. The first step is to have your son identified as gifted and that will give you a better idea of his needs.

We had the situation in my sons' school where the gifted pullout was not up to our expectations. This year the curriculum was changed and it's much more academic. So if you don't like the gifted pullout, know that it can be changed.

In our district, the pull-out program requires parental consent but is not part of an IEP. So, the pull-out really is just a pull-out unless you personally request and pursue an IEP.