The way to pick out a picture book is to spend time looking at the best of them

Splashy pictures and unusually large or small size are all too often the factors that persuade parents and grandparents to buy a particular children's picture book. But too much emphasis on these characteristics, along with haste in choosing a book, may result in not making the best choice. Ethel Heins, former editor of the Horn Book Magazine, a magazine which publishes reviews and essays on children's books, says that first of all parents ``must be willing to invest some time and some interest [in picture books], and surround themselves with good picture books.''

She suggests a parent go to the library and spend several hours going through books that have stood the test of time. ``The [children's] librarian is the person who should know the basic picture books and be able to help the parent,'' Mrs. Heins says.

On this initial trip to the library, parents should leave children at home. It's easier to browse, examine the card catalog, and talk with the librarian if little ones aren't underfoot.

Sonia Landes, a language and literature consultant at the Buckingham, Browne & Nichols School in Cambridge, Mass., agrees that one of the best ways to become reacquainted with picture books is simply to spend several hours reading them -- in a bookstore or in the library.

Although she believes that the librarian will know what is good and what children are reading, she also says that ``the parent is very important in the decisionmaking process. The parent knows the child best, the parent is the one who will be reading the book to the child.''

While looking at picture books, Dr. Heins recommends a parent ask some of the following questions:

Is the story line original and is it imaginatively executed?

Do the text and the illustrations result in a whole?

Is the text itself worth listening to?

Are the illustrations appropriate for the story (i.e., if the story takes place in Colonial America, are the illustrations set in the same time period)?

Do the illustrations go beyond the words, but also faithfully interpret the text (i.e., do the illustrations show the reader more than the text tells him, but also reflect the tone of the story)?

Do the illustrations extend the emotion and action of the text (e.g., if the story is about the fast-paced life in the city, do the illustrations reflect the hustle and intensity of city life)?

By asking these questions, a parent should be able to begin to discriminate between the good books and the bad.

``In picture books for the young child, board books [up to age 2], there is rarely a story line. Instead each illustration is a dramatic scene,'' says Mrs. Landes. ``The old-fashioned static figure of a solitary object, a ball or a cat, is out. Children want to see a mirror of themselves reading with Daddy, playing with blocks, or eating and spilling their dinner.''

One picture book author Landes recommends is Helen Oxenbury. Another is Eric Hill, whose ``Spot'' books -- books with surprises under the flaps -- make children laugh out loud.

As a child becomes a little older (aged 3 to 6), the story line becomes more important. The story should be told in part by picture, in part by the words. Landes says that the ``sign of a good picture book is that the pictures tell one story, the text spins another. Together they weave into one whole.''

The necessity for the illustrations and the text to intermesh is one reason Landes feels that, surprisingly, many wordless picture books, like ``A Boy, A Dog, A Frog, and A Friend,'' are more difficult to read.

``They require a close look. Every detail of plot hinges solely on illustrations with no help from words.'' ``The concept,'' she says, ``is a wonderful one, but often for a more experienced reader.''

If you are still not sure how to choose a good picture book, Landes suggests a further visit to the local library, ``not only for storytelling and borrowing books and tapes, but for book lists.''

Many libraries have reading programs, and if you or your child is not quite ready for a structured reading agenda, the librarian should also have some book lists readily available.

``There are also some excellent guidebooks to help you in your search for good books,'' Mrs. Landes says. Three books she recommends are ``For Reading out Loud!,'' by Margaret M. Kimmel and Elizabeth Segel (Delacorte Press), ``The Read-Aloud Handbook,'' by Jim Trelease (Penguin), and ``A Parent's Guide to Children's Reading,'' by Nancy Larrick (Doubleday). Picture books for children: old and new

Classic picture books are as treasured as classic novels; the old ones are still read and loved. Parents have a double task; to read the classics and to pay continuing attention to the newer ones. Listed below are books for a good start. The Tale of Peter Rabbit, by Beatrix Potter. New York: Frederick Warne. $3.95. Where the Wild Things Are, by Maurice Sendak. New York: Harper & Row. $10.95. Sylvester and the Magic Pebble, by William Steig. New York: Windmill Books. $4.95. Corduroy, by Don Freeman. New York: Viking. $9.95. One Monday Morning, Uri Shulevitz. New York: Scribner's. $11.95. And to Think That I Saw It on Mulberry Street, Dr. Seuss. New York: Vanguard Press. $6.95. Make Way for Ducklings, Robert McCloskey. New York: Viking. $11.50. The Story of Babar, Jean De Brunhoff. New York: Random House. $5.95. Miss Rumphius, by Barbara Cooney. New York: Viking. $12.95. Millions of Cats, by Wanda G'ag. New York: Coward-McCann, $7.95. Anno's Alphabet, by Mitsumaso Anno. New York: Crowell. $11.95 Goodnight Moon, Margaret Wise Brown. Illustrated by Clement Hurd. New York: Harper & Row. $8.95. The Snowy Day, by Ezra Jack Keats. New York: Viking. $10.95. Once a Mouse, Marcia Brown. New York: Scribner's. $12.95. Mike Mulligan and His Steam Shovel, by Virginia Lee Burton. Boston: Houghton Mifflin. $11.95. Lion, by William P`ene du Bois. New York: Viking. $12.95. The Three Robbers, by Tomi Ungerer. New York: Atheneum. $1.95. An Anteater Named Arthur, Bernard Waber. Boston: Houghton Mifflin. $9.95. The Happy Lion, by Louise Fatio. Illustrated by Roger Duvoisin. New York: McGraw-Hill. $10.95. Frog and Toad Together, Arnold Lobel. New York: Harper & Row. $8.95.