Iphoto-how do I move a single photo from one album to another existing album

Words are critical

you can not "scan a photo into iPhoto" iPhoto has no scanning capabity - you scan with scanning sofware and import into iPhoto. Is this what you did?

In iPhoto folders do not contain photos - they contain other folders or albums - photos are in events (or photos view) and can be places into albums (a logical placement - the photo is still in the library and is referenced by the album not moved to it)

What exactly do you have and what do you want to do?

In general to move photos between events you would flag the photo(s) and go to the target event and add flagged photos to the selected event

LN

it to the relevant folder

Are you referring to an Event or a folder in the left hand pane of iPhoto as Larry mentioned? Be more specific in describing what you're trying to accomplish.

OT

In iPhotos, you used to be able to move a single photo into an album - now when I try to do that, it includes the entire "moment" - so if 10 photos are in the "moment" all 10 move, instead of just the one that I want to move...

Ah, I figured it out - if you use the + button that is directly over the "moment" section, it moves the whole "moment" and if you go to the top of the Photos section and use that + it will move only what is selected.