Shrek!, by William Steig (Michael di Capua/Farrar, Straus and Giroux, $13.95; ages 3-up). Is that Shrek as in wreck or as in shriek? Either way Shrek is a fright. Green-skinned, buck-toothed, with a face covered with bumps, pocks and polyps, ugly in a friendly Wallace Beery way, Shrek is simply your average happily adjusted monster, easy-going and unmalicious, if not precisely kind-hearted. And, oh yes, he can also breathe fire. All nature shrinks from him, but he couldn't care less.

"One day Shrek's parents hissed things over and decided it was about time their little darling was out in the world doing his share of damage. So they kicked him goodbye" -- and Shrek goes off to seek his fortune.

Along the way he swallows lightning during a storm, is amused by an irascible dragon who unfortunately tries to devour him, and suffers a terrible nightmare in which he believes himself "in a field of flowers where children frolicked and birds warbled." Some of the little ones even hug and kiss him. Happily, it's only a dream.

Eventually, like any chivalric knight-errant, Shrek goes on a quest, overcomes myriad obstacles, and finally attains his destined beloved, to whom he sings: "Your horny warts, your rosy wens,/ Like slimey bogs and fusty fens,/ Thrill me." Naturally, Shrek and his Sleeping Ugly live horribly ever after.

This counter-clock fairy tale is sure to enchant any child lucky enough to read it. Text and illustrations are relatively simple, but Shrek! is such an ingratiating, cheery book that no one will be able to resist it. Not Steig's peak (that remains that strange picture book, The Amazing Bone), this is a modest achievement, but a perfect one.

A Day with Wilbur Robinson, by William Joyce (Harper & Row, $13.95; ages 5-up). In Dinosaur Bob author-illustrator William Joyce paid tribute to several icons of the 1920s and '30s: Scott Fitzgerald, Little Orphan Annie comics, sleek Raymond Loewy industrial design, Andy Hardy movies and baseball. The result was one of the best picture books of 1988. A Day with Wilbur Robinson may be even better, for this time out Joyce memorializes a childhood in the '50s, grade-B Martian invader flics, populuxe furnishings, "space-age" products and seemingly the last era of traditional family life.

The action is simple: A bespectacled blond kid goes to visit his best friend Wilbur Robinson whose "house is the greatest place." Golly, Beaver, is it ever! Twin uncles -- looking like refugees from a Larson cartoon -- hide in the shrubbery. A tentacled creature takes your bag at the gigantic front door. The household cats are Bengal tigers. Uncle Gaston reposes in a family cannon. A full-size locomotive chugs through the living room.

Over this happy tableau, though, a pall suddenly descends: Grandfather's false teeth are missing! The kids naturally check first with Uncle Judlow who lounges on a throne wearing his brain augmentor while enunciating brilliant insights like "Mississippi spelled with o's instead of i's would be Mossossoppo!" Uncle Judlow being no help, the boys then look for Cousin Laszlo, whom they find demonstrating an anti-gravity device -- as a flying saucer lands in the distance.

Joyce's illustrations for all this are wonderfully kooky, entirely his own but reminiscent of what a Chris Van Allsburg might draw if he'd spent the evening reading Daniel Pinkwater's The Snarkout Boys and the Avocado of Death. After David Macaulay's much more demanding Black and White, this may be the best picture book of the year (so far, anyway). But why did they leave out the illustration -- a mad scientist directing a electric rays at a jack o'lantern -- used as a cover for a recent issue of Publishers Weekly?

Monsters, by Russell Hoban; illustrated by Quentin Blake (Scholastic, $12.95; ages 5-up). When the team that gave the world that devil-may-care children's classic, How Tom Beat Captain Najork and His Hired Sportsmen, gets back together, it's time to call the kids, snuggle up and get ready for a treat.

A treat with something of a sourball flavor, though. Young John -- who looks about 9 or 10 -- loves to draw monsters, nothing but monsters, with deadly horns, fire-breathing snouts, laser weapons constantly at the ready and ugly dispositions. "All of John's monsters were violent. They fought with passing strangers and random spacecraft and they fought with one another, and if they found themselves alone they made threatening noises to themselves while waiting for somebody ugly to turn up. "GNGGHHHHH!" they said, "NNARRRRGH!" and "XURRRVVVV!" These are guys who would be right at home on William Steig's Rotten Island (whose denizens are much meaner than the comparatively winsome Shrek).

Naturally, John's sweet-tempered, understanding parents are a bit worried about the obsessive character of their son's artwork. They urge him to draw lions or tigers, but John won't hear of it. In fact, he embarks on a mammoth project, involving long rolls of brown wrapping paper. It takes several yards just to draw a scaly, spiked tail, which seems disturbingly all too realistic. A concerned Mom and Dad talk to their son's art teacher who proves no help at all: Mr Splodge only says, "It's very well done" and adds, "It almost jumps off the page at you."

By this point, astute readers young and old will probably see what's coming. John's parents blithely go on and consult the well-meaning but dimwitted psychiatrist Dr. Plunger. He urges John to finish his monster drawing. John asks disingenously, "Are you sure you want me to?"

Then, "in the waiting room Mom and Dad heard a noise like two or three heavy metal rock bands all playing at once. There wasn't a lot of music to it, it was mostly thumping and bumping and crashing around." When John comes out of the doctor's office, his folks asks if he's done with drawing monsters. "Drawings," answers the boy, as the door behind him slowly opens. "Who needs drawings?"

Hoban's prose is perfectly cadenced as usual, Blake's pictures are wonderful (he even reproduces the school notebook paper that John uses), and the story ends with a nice snap. But there's something cruel to it, more like late Roald Dahl (whom Blake also illustrates) than the usually wistful Hoban. The destruction of Dr. Plunger seems heartless, and there's even a hint that John's parents may become the monster's next victims.

This is a conte cruel then, but a surprisingly suggestive one: Does art sublimate our violent impulses? In what way does art escape from its creator? Are we its servant or its master? Should we tamper with our deepest urges and needs? Children's literature has always dealt with fundamental matters, so be prepared to talk about some Big Questions with your young readers.

The Magic School Bus: Lost in the Solar System, by Joanna Cole; illustrated by Bruce Degen (Scholastic, $13.95; ages 5-10). Miss Frizzle's class is always going on field trips in that dilapidated bus, the kind that wheezes and huffs and shudders but still manages to keep on rolling. Still this is no ordinary vehicle we're dealing with here. After all, the Friz's earlier classes have somehow journeyed inside the human body, through the city water works and even to the center of the earth.

The Magic School Bus series blends facts and fun about equally -- "Pee-Wee's Playhouse" meets "3-2-1 Contact." Drawn in cartoon style, Cole-Degen make each page do at least triple duty: The text relates the action; speech balloons track the wisecracks and complaints of the long-suffering pupils of La Frizzle; and margins lay out some simple scientific information in the form of pop-quiz questions with student answers: "Why is Mars red? By Arnold. Mars looks red because there is a lot of rusty iron in its soil."

In The Magic Schoolbus: Lost in the Solar System Miss Frizzle's class, disappointed at finding the planetarium closed, blasts off through the stratosphere to explore the moon, the asteroids and the planets. The light gravity of the Moon naturally proves a great playground for the restless kids. Giving some drama to the planet-by-planet tale, Frizz is inadvertently marooned in space and the magic school bus itself saved from interstellar disaster by a snooty little girl.

The After-Christmas Tree, story by Linda Wagner Tyler; pictures by Susan Davis (Viking, $12.95; ages 2-8). This is the fifth in a series of collaborations between Tyler and Davis, both of Washington; earlier albums include The Dinosaur Who Lived in My Backyard and My Brother Oscar Thinks He Knows It All. They all share certain qualities: an easy, gentle text (usually one sentence per page) and cool subdued watercolors of an ingratiating simplicity. (The Washington Post's readers will recognize Davis's work from her illustrations for Henry Mitchell's columns devoted, about equally, to grousing and gardening.)

At first I resisted these books, finding them over-simple, a tad sentimental. Still, last year I decided to test The Dinosaur Who Lived in My Backyard on my two sons, then aged 2 and 5, and probably the greatest living authorities on animal life of the Jurassic era. They loved it. In the story a boy and girl reminisce about the apatosaurus that lived in their backyard thousands of years ago; the pictures show a lime-green, soft-toy-like beast romping among the swing sets or running wildly from a tyrannosaurus rex (and who wouldn't?). The whole book was exceptionally soothing, better than a snack and a session of "Duck Tales" for calming half-wild 4 o'clock savages.

The After-Christmas Tree again shows the Tyler-Davis flair for a child-pleasing tale. All kids, and most adults, are sad when the Christmas season ends and it's time to take down the bejeweled and bebaubled tree. To ease the rude transition back to ordinary life, Tyler-Davis picture a family that decides to hold an after-Christmas party, where kids ice-skate and play outdoors, then come inside to deck the boughs of the now bare tree with nuts, birdseed, berries, strings of popcorn and other goodies favored by birds and squirrels. The group installs the redecorated tree in the snow-covered front yard, where it looks almost as beautiful as before. Then, as everyone lounges in the living room sipping hot cocoas, the birds of the air and beasts of the field come out to enjoy their unexpected winter feast.

Yes, The After-Christmas Tree is a bit corny, but it has a sweetness and innocence that is endearing and a useful message as well. I expect that this January at least one local family will be sticking a scraggly Douglas fir, covered with nutty treats, out in the snowy front yard.

Michael Dirda is children's book editor of Book World.