“So, blog is written for the teen & parent is like a voyeur.”
Yes, I think this can work. So your ideal reader is a teen, and the parent reads primarily to see whether it’s helpful for their child.
Your point about teens not liking parent pages is a good one, too. This would be an extra reason to target the teen rather than the parent (and rather than both).
I know I’m a little ahead of the schedule, but as this is an essential point it’s good to start thinking about it, so you’re comfortable with your choice in module 2.
Enchant readers. Woo customers. Win business.