"This is my personal observation of the few hundred homeschoolers I have known.
Scientific discovery does begin with anecdotal personal observation. Perhaps this phenomena will catch the interest of those qualified to study the matter."
Peer review is the lynchpin of building on scientific discovery - challenging assumptions
To wit: I submit to you that kids with true ADHD/ADD (I believe it's overdiagnosed in a big way - but I'm not a doctor or a psychologist) aren't homeschooled as much because the parents can't teach them (or find it very difficult) so they enroll them in public school (not all - but a high proportion) where it becomes societies problem (that's not a criticism, by the way) and the resources of society, through public schools can be deployed to address the need.
Same thing is true with kids with autism, and many other special needs and handicaps. They go disproportionately to public school.
Yes, I'm sure there are exceptions, but I have a little experience in this area - not my own child, but family (to add my own anectdote).
So, once again we have a self-selecting statistic involving homeschooling.
I am all for homeschooling (gotta keep saying that so people don't think I'm hostile towards it!) but the utopian characteristics of the population of homeschooled kids described by many posters on this and other threads is only possible because those poor performing parent teachers, or poor performing homeschool kids, or kids with special needs default back to public school more often than not. This "culling" of the statistical pool would also be a factor in improving the apparent performance of homeschoolers as a group, compared to the public school population - taken collectively.
As to fat kids.....I know a fat homeschooler so my anecdote is just as valid as anyone elses on this.
My youngest one, currenty being homeschooled, is ADHD. He s homeschooled precisely BECAUSE she's ADHD, and the local public school couldn't deal with her. Rather than accept her assignment to a "special" school where she would be warehoused with other kids with even bigger problems than hers, we decided to homeschool her alongside the other two.
She's making very good progress with the individualized attention
One common factor in all homeschooling environments: the parent is passionate about having the kid learn (otherwise the parent would not be homeschooling). This is THE major contributor for success, in either a homeschool or conventional-schooled environment