rough and dirty links that seemed helpful/useful while researching:

wpdesigner.com/…bring-life-to-your-blog-using-conditional-tags/

wordpress.org/support/topic/125828

schloebe.de/wordpress/is-subpage-of-plugin/#english

erik.range-it.de/wordpress/plugins/is_child/

thingsbymike.com/wordpress-different-sidebar/

sporkfancier.com/collapsing-page-menus-plugin

what finally did it, the easiest way, was the collapsing menus plugin. that’ll hold my nonprofit’s site for now. when i come in next week i’ll create individual sidebar.php files, and customize each per the instructions on the plugin’s page, which seems mighty simple.

oh, yeah: i finally got my nonprofit’s site redesigned. (kudos to me =)