The students choose a picture or photograph and decide what the person may be thinking or saying. They then draw a speech bubble, cut it out and stick it onto the picture. Of course, speech bubble texts may also be witty.
Variants: speech-bubble dialogs with two or more persons / Art pictures instead of photos (Mona Lisa etc.) / smileys (emoticons e. g..: or instead of photos / copy of a Comics with the writing from the speech bubble deleted so students can create their own versions, then compare them.