If for example you want the youth minister to only be able to login and edit the youth ministry page, you must do the following:

STEP 1

Login and click on System>Users  in the user menu at left of site.

Click on the persons name you want to give editing privileges to.

In the Role select box, choose Author.

Click Save at top.

 

STEP 2

Now click the PAGES button in the user menu on left of website.

Click the name of the page you want to assign this user to.

In the Author dropdown box, select the user you want to edit this page.

Click Save at top.