Interested in cheerful looks at the quest for knowledge? In time for the new school year, several lighthearted picture books that celebrate learning and the classroom.

Chicken Big (Chronicle, 36 pages, $16.99, ages 4 to 7) by Keith Graves - Even the smallest chicken (and "not the sharpest beak in the flock") learns by the end of the story that the kindhearted, newly hatched, humongous yellow chick is not an elephant, an umbrella or a sweater - even though he is enormous and keeps the little chicks dry in the rain and warm in the cold. Graves' tale is a funny lesson in trial-by-error discovery, with equally entertaining cartoonlike illustrations.

Kindergarten Cat (Schwartz & Wade, 40 pages, $16.99, ages 3 to 7) by J. Patrick Lewis, illustrated by Ailie Busby - A tabby cat found on the playground by Mr. Bigbuttons, the janitor, becomes the kindergarten mascot. She entertains the children and even answers a few questions in the warm and fuzzy story by central Ohio author Lewis, who works in a bit of elementary wordplay.

Library Mouse: A World To Explore (Abrams, 32 pages, $16.95, ages 5 to 7) by Daniel Kirk - An adventure-loving mouse and her more conservative friend, a mouse fearful of heights, pair up to explore the upper shelves in the library - where they discover Egyptian artifacts, a toy airplane and more. He learns to take a few risks, and she learns the value of research, in the sequel to Kirk's excellent Library Mouse from 2007.

Late for School (Grand Central, 32 pages, $17.99, all ages) by Steve Martin, illustrated by C.F. Payne - On a CD, comedian Steve Martin sings Late for School from his bluegrass album The Crow - about a boy's mad, late-for-school dash that includes falling into a swimming pool, catching a lift from a kite and pushing his grandma's face into a pie. The energy is matched by Payne's lively paintings. The book is a hoot from start to finish.

- Nancy Gilson