It's a genuine phenomenon: Paint by Sticker Kids books provides hours of creative, mess-free, and screen-free fun around topics that kids love. And at the end of it, kids--and their proud parents--have wonderful works of art to display or give away. With the obsession for mermaids, unicorns and other magical creatures showing no signs of letting up--and with Disney's live-action film of "The Little Mermaid" slated to release in November,...