Cool distortions, a perplexing parallel pattern, afterimages, 3-D foolery, flip-flopping faces, and other optical illusions will “trick” you into seeing what isn’t there. “More complete and informative than most children’s books on the subject, this entertaining, enlightening volume will be helpful for projects and fun for browsing.”—Booklist. “High quality color photographs... simple language...fun to read.”—Mathematics Teacher.