pantsonhead

Currently WordPress does not provide the ability to change the post that an item in the Media Library is attached to after it has been set. This plugin allows editors to change the parent post to another post.

Change Media Parent

Allows editors to change the parent post of an attachment after it has been set.

James Irving-Swift

Electric Studio

Adds a filter in your wp-admin that allows you to choose a parent page so that only the children of that page will be shown. Very useful if you have a lot of pages! 
Thank you to Brian Krogsgard for the changes in version 1.3 (Twitter: @Krogsgard)

Filter Pages by parent in admin

Filter pages in the wp-admin by their parent pages

Change Media Parent vs Filter Pages by parent in admin