Once you have your rectangle text box open-You will see directly above the photo an 'A' Click on the A to open your font menu to choose size/type of font.

put your cursor over the area of photo you want to add text to and LEFT CLICK and then DRAG your + sign left to right to open your text box.

Your cursor will now change to a + sign.

Scroll down for the 'ANNOTATE' option and Choose TEXT.Once on the des top look up at the top of your screen for the menu bar again for the 'TOOLS' menu.

You drag the photo by going to the photos section of IPhoto-left click on the photo once until it's highlighted with a yellow border-left click again and HOLD DOWN your left click and drag the photo to you desktop (while dragging you will see a red and green button appear.

drag your photo out of IPhoto onto your desktop(I have the 08 version-To see your version of IPhoto- Open IPhoto, then look at the top left corner of your Mac screen next to black Apple logo, click on 'Iphoto', click on 'About Iphoto' then window that pops up tells you your version in the title).

How to write text on a picture on mac