The Best Board Books of the Season SIMMS TABACK'S DINOSAURS Written and illustrated by Simms Taback. 20 pp. Blue Apple Books. $12.99. Board book; ages 2 to 4 Taback, who won a Caldecott Medal for "Joseph Had a Little Overcoat," and a New York Times Best Illustrated award for "There Was an Old Lady Who Swallowed a Fly," died last year, which makes this new foldout board book one of the last books he worked on. Here, large type and oversize foldouts create an excellent introduction for the youngest paleontologist. Each dinosaur is described by a few characteristic traits, clearly reflected in the unfolding artwork. Taback's trademark hand-drawn lines create easily recognizable, vibrant creatures that will elicit appreciative oohs and aahs. HAROLD AND THE PURPLE CRAYON Written and illustrated by Crockett Johnson. 34 pp. HarperFestival/HarperCollins Publishers. $7.99. Board book; ages 3 to 6 Board books are for babies and toddlers - at least according to some preschoolers. But many preschool favorites are translated into board book editions nonetheless. "Harold and the Purple Crayon," the beloved story about the power of a boy's imagination, is most definitely a story for preschoolers and kindergartners. Both the concept and the relatively heavy text are over the heads of most toddlers. That said, for the 4-year-old devotee, there's nothing wrong with a sturdier edition, and there's always the precocious 2-year-old to consider. HIPPOPPOSITES Written and illustrated by Janik Coat. 38 pp. Appleseed Books. $14.95. Board book; ages 1 to 4 Thank heaven for hippos, creatures unwieldy in both size and name, and go-to subject for so much children's literature. Jack Prelutsky's "I've Lost My Hippopotamus," published earlier this spring, is one recent standout example. "Hippopposites" - say that three times fast - is a welcome addition to the pile. Images illustrating opposite pairs are set on opposing pages, each starring its own hippo. "Heavy" features a hippopotamus submerged underwater; "light" shows him aloft in a hot-air balloon. But the book goes beyond the obvious pairings, and the illustrations are superlative in concept and execution. "Positive" and "negative" flip black-and-white images of the same hippo. "Squared" makes him all angles; "rounded" renders him supple. Interactive additions give the "soft" hippo a downy pink coat; in "rough" he appears in burlap. Isn't a beaten-up baby board book the opposite of an elegant grown-up coffee-table book? Not in this case. Illustrated by Nancy Carpenter. 30 pp. Houghton Mifflin Harcourt. $7.99. Board book; ages 1 to 3 Another big-book to board-book adaptation, this one fits the toddler format. With a few text-heavy exceptions, the pages pair a simple sentence or two with images. And those images, precious and small scale, illustrate the story of a bear who loves floating and sailing his boat along Huckleberry Lake. Until one day, the boat is suddenly too small. "It is a little boat's destiny to keep sailing on a blue, blue lake," the bear laments. But Little Bear, now a Big Bear, comes up with a solution: He must find another little bear to enjoy the vessel. If only every small creature's ambivalence about getting older were so easily resolved. LITTLE BEE Written and illustrated by Edward Gibbs. 24 pp. Little, Brown & Company. $8.99. "Little bee, little bee, why do you flee?" is how this humorous page-turner opens, with a hat tip to Eric Carle's "Brown Bear, Brown Bear, What Do You See?" The next page discloses the answer: "Because there's a hungry frog chasing me!" The frog's gleeful pursuit soon comes to an end, however, when the frog in turn starts to flee. "Because there's a scary snake chasing me!" And on it goes, with each predator becoming the pursued in a less-than-feel-good take on the old Circle of Life. The best is the kicker, when the granddaddy of all chasers, the big bad human hunter, gets what he deserves. Readers may not see it coming, but they'll enjoy the gotcha moment when it arrives. Written and illustrated by Belle Yang. Candlewick Press. $6.99. Published with a companion volume ("A Nest in Springtime: A Bilingual Book of Numbers"), this delectable ode to springtime features a fluffy bunny threesome as they explore "yummy green grass" and a "spray of blossoms in the sky" ("That's a rainbow"). With Mandarin Chinese characters on the left and English on the right, along with a Pinyin glossary and guide to Chinese tones in the back, the book will no doubt sate the needs of Tiger Moms and multicultural families alike. Happiest may be the child readers themselves who will relish the delicate gouache illustrations and the sensorial lushness of spring. Written and illustrated by Sandra Boynton. 22 pp. Workman Publishing. $6.95. Board book; ages 1 to 5 Sandra Boynton squeezes a good deal of humor out of animals looking startled, bemused or thoroughly exhilarated by the ridiculous things their bodies do, and this latest board book is no exception. With its pitter-patter text ("Gitchy-gitchy goo gotta gitchy-gitchy goo gotta gitchy-gitchy goo gotta ready set go!"), the book practically begs to be sung or at least rapped aloud. But not at bedtime. SEVEN BLIND MICE Written and illustrated by Ed Young. Philomel Books. $8.99. Board book; ages 3 to 8 The board book is a fine format for the sumptuous artwork of Ed Young's Caldecott Honor winner. Even if the story's deeper meaning will be lost on teething toddlers. One by one, a group of colorful mice traipse across a black background to investigate a mysterious object. Each sees only one part and imagines, erroneously, what the whole must be. Only together are they able to view the object in question accurately and in its entirety. The Mouse Moral: Knowing in part may make a fine tale, but wisdom comes from seeing the whole. The smallest readers may see only scampering mice, but that shouldn't diminish the experience. TRAINS GO Written and illustrated by Steve Light. 16 pp. Chronicle Books. $8.99. Board book; ages 6 months to 5 years Steve Light's animated and elongated guide to trains was born to be a board book, even if it did have an earlier incarnation in paper. Perfect for a toddler to spread across his lap, "Trains Go" is made to be read aloud: "The streamliner goes Wo Wooo Woooooo Wooooooooooooooooooooooooo!" Comfortable though the Acela Express may be, this gorgeously illustrated old-timey ode to train travel makes you long for the days of "Clang clang clang toot toot!" Now children, too, will know what they're missing. Written by Phillis Gershator. Illustrated by Jill McDonald. Barefoot Books. $14.99. With oversize die-cuts on every other page, this look at a young girl's backyard garden allows children to play peekaboo and guess who as they encounter on the next spread, the bees, birds and frogs that live there. McDonald's occasionally whimsical mixed-media collages are engaging, colorful and busy with detail, and Gershator's simple rhyming question-and-answer text is appealing and age appropriate, making this a nice introduction to outdoor critters for young children.