How do I hide a series of photos so they do not show in my iPhoto Library?

CTRL-click (right-click) on the photo in question. Near the bottom of the contextual menu is "Hide Photo". Cheers!

To make hidden photos reappear, go up to the View menu and place a check mark beside "Hidden Photos". When the hidden photo reappears you will see a red "X" in the upper right corner.

If you want to permanently make a hidden photo visible again, do the above and then CTRL-Click (right click) the photo and select "Unhide Photo."

Hope this helps. Cheers!