Winni Allfours

Partisans of ponydom will welcome this characteristically zany picture book by Cole ( Tarzanna ; Supermoo ), as usual replete with abrupt plot twists. Winni, pressured by her vegetarian parents to eat greens at the school cafeteria, gets a brainstorm when a cafeteria worker remarks, ``You'll turn into a horse if you keep eating so many carrots.'' Winni, who loves ponies and has been forbidden to keep one of her own, determinedly devours all her vegetables--and then some. ``Very . . . slowly . . . things . . . started . . . to . . . happen,'' writes Cole as small watercolors portray Winni's transformation: she sprouts ears, a muzzle, shiny hooves and a tail until she's a dapple-gray pony--with blonde braids in her mane. Naturally, she's no average steed--as a racer she's unbeatable, and her name couldn't be more appropriate. Why Winni uncomplainingly allows herself to be kidnapped by a crooked racehorse trainer goes unexplained, and Cole's narrative is often choppy, but the spreads communicate the necessary elements and the perky ponies have a plump, cuddly charm. Winni's ultimate refusal to turn back into a girl (despite her mother's promise to buy her a pony) will trouble only hardened neigh-sayers. Ages 5-9. (Mar.)