He is also starting to ask questions about why I dont attend the meetings anymore.
Good for him. It is ironic that your son is six and that there at least two yearbook examples of six-year olds that have been baptized -- which shows the society's position on the matter. That's awfully close to infant baptism, in my opinion.
I believe he's old enough, however, to under this 11 minute read (for grown-ups). At least, the concept of it all. Called The Great Watchtower Contradiction, it's mild enough for new ones to understand -- strong enough to give even the most seasoned JW serious pause.
Len