Mermaid children explore a beautiful world, both above and below the waves.With a beguiling flash of a tail, readers are invited on a dusky, pre-dawn ocean tour. Three young mermaids sleepily awaken: "Today is a good day…A good day for exploring the colors of this world." And what colors! As the day begins, the trio sit on the rocks and gaze up at a glorious, blood-orange sunrise. The mermaids move through the day, encountering a different color in each scene. They glide through an orange-hued school of fish, dive through green "underwater gardens," and leap through blue skies and waves. The three enjoy a wonder-filled day until twilight, when at last the sky and the water turn violet, completing the rainbow and reminding them that it's "time for quiet." The mermaids head for bed-a cozy nest of bubbles-perhaps to dream of vibrant days ahead. The rich, jewel-toned illustrations are appealing and provide a welcome opportunity for discussion about the different colors of the rainbow. Sparkling wordplay and inspired use of alliteration ("Blooming bright skies surprise our eyes," "a swimming school of jewels down under") make for a lovely read, perfect for a bedtime tale or a storytime read-aloud. One of the mermaids is pale-skinned and blond-haired and has a limb difference; the other two are tan-skinned.A delightful, rainbow-colored way to spend the day. (Picture book. 2-6)