Wordpress : problem of structure

[zibizibi]

Hi everyone,

I wonder what's the best way to organize my WordPress website :

I have three major types of visitors : child, teen, adult. For each there's a particular horizontal menu on top, containing links which display particular kinds of posts (ex: news related to children if you're in the child section) and a particular style affecting the entire layout.

Should I use custom menus? Should the child, teen and adult sections be Pages each using a different Page template? Or is there a better solution ?