School Selection

I live in Prachinburi province and my boy is now entering the sixth grade.

The school he attends seems to be okay, and he does well, but I would like to find something better for 7-12.

There does not seem to be anything worthwhile in the area, so we are looking at Bangkok, preferably on the NW side to avoid as much traffic as we can.

I would like recommendations on both specific schools, what resources are available for selecting schools, and what particular schools to avoid.

Thanks,

Dave