This is a known issue in Drupal core.
#283045: Allow top-level pages to be removed from books

I am pretty sure the functionality will not be back-ported to D6 so I am going to add this feature to the 'Order' tab.

Comments

jrockowitz’s picture

jrockowitz commented
Status: Active » Needs review
jrockowitz’s picture

jrockowitz commented
Status: Needs review » Closed (fixed)

Tested on a production website and included in the most recent release