Those of us who work with kids, be it with reading, swimming, or Wii-ing, know one important rule of thumb: first we have to get their attention. In the book world, in addition to the word underwear or the newest installment in a hot new series, movable books — with tabs to pull, wheels to turn, or giant T. rexes to pop out in all their three-dimensional wonder — are a surefire way to immediately capture kids' attention. Then comes the corollary: now we have to hold that interest.

No matter how visually stimulating a particular book may be, the medium alone will not enthrall youngsters. Just as kids don't love all films loaded with special effects or all computer games, neither do they love or respect all movable books. I first saw this phenomenon in the mid-1980s when I was a junior high librarian. At that time a spate of pop-up books, mostly nonfiction, hit the market. A couple, such as Heather Couper and David Pelham's The Universe (which depicted the Big Bang with, well, a big pop-up bang) and Jonathan Miller and David Pelham's The Facts of Life (and, yes, a penis popped up), had received critical acclaim, both appearing on ALA's 1985 Best Books for Young Adults list. I wondered how kids would respond: would they view these books as dismissively as adults once had, considering them "toy books," or would they take them seriously as sources of information?

In order to see how young adults of the 1980s would respond to this new-to-them format (movable children's books have been in existence in one form or another since the 1700s), I purchased every pop-up book relevant for this age I could find and circulated them in the library. Of course, being junior high students, these youngsters sometimes brought their own sense of immature play to the process. Often I saw young adolescent boys sweeping through the library holding Sailing Ships by Ron van der Meer and Alan McGowan high above their heads, wide open to a pop-up of some vessel under sail, and dipping the book through the air as if it were riding forty-foot waves. These same boys opened The Facts of Life to a picture of sperm (which resembled a nest of squirming snakes) and in a faux Freddie Krueger voice snuck up on unsuspecting girls, whispering, "I'm gonna get you!" And then there was The Royal Family Pop-up Book, a silly cross between a commemorative edition and a cheap souvenir: as Charles and Di wave from a balcony on their wedding day, small union jacks pop up; the royal couple picnics with young Prince Wills in Australia; and Queen Elizabeth herself flips hamburgers in front of Buckingham Palace. The book was universally treated as a kind of static paper doll collection as young girls, in falsetto voices, played out the scenes: "Oh, Charles, would you go change Wills's nappy?" "Charlie, I'm hot here in Australia. I think I'll go change clothes. What should I wear?"

But the books these young teens came back to were the ones that in my mind began to create a template for what makes a good pop-up book. Like picture books, pop-ups must meld illustration with text in order to produce something greater than their individual parts. In addition, the paper mechanics should serve a pur-pose beyond visual stimulation, enhancing theme or content in some meaningful way. These features characterized the pop-up books the kids continued to read after the fascination with the format died down.

One such book was Jonathan Miller's The Human Body. This three-dimensional presentation shows what no flat pictures or illustrated transparencies can: the relational position of various organs to the skeleton. Football players, particularly, were fascinated with the rib cage; they mentioned over and over that now they could see why breaking a rib might be dangerous rather than just painful. In Sailing Ships, these youngsters studied the models of ships, seeing and understanding the rigging of a barque, an interest sparked by the renovation of the square-rigged Elissa in Galveston. And, in awe, they would open The Facts of Life and caress a plastic transparency that covered a baby moving through the birth canal. As one young girl told me: "I knew how it got in there; I never really knew how it got out."

And the ridiculously static Royal Family Pop-up Book? After the first few days of play, it never circulated again.

The movable features of any book should be there for a purpose. As in the favored books above, the medium is a large part of the message. Look at Marion Bataille's ABC 3D. Using only three colors (black, white, and red), Bataille emphasizes the shape of each letter, slyly letting many morph into the next one. For example, O and P appear on the same page; cover that page with a translucent one, and bold rectangles appear over the letters, turning the O into a Q and the P into an R. Open up the page for E, and this vowel pops up in all its rectangular glory. Open further, and the base of the E disappears, turning the letter into the next in sequence: F.

Like so many fine children's book illustrators, those dealing with paper engineering may choose to look at similar ideas quite differently. Like Bataille, David A. Carter, in his pop-up book Yellow Square, also elects to concentrate on shapes. His version asks youngsters to find a yellow square of cleverly hidden paper in forms resembling the work of great artists such as Alexander Calder or Christo. As with multi-layered texts, this near-wordless book creates many avenues for enjoyment and contemplation.

Pop-up art can also take on literary elements. High on the wow factor is the swirling black tornado rising up from the page to begin Robert Sabuda's retelling of The Wonderful Wizard of Oz. It's as much of a hook for the reader as an exciting opening line in a novel.

Paper mechanics may also augment the overall narrative. In Sam's Sandwich, for example, young Sam is making a sandwich for his sister. Each addition, from lettuce and cheese to a bug and a worm, builds the rising action for both his culinary creation and the story as a whole. But Sam's Sandwich misses one important ingredient: the text falls short, and the paper engineering overshadows the words. In pop-up books, as in all others, text does matter. Just as some picture books are too painterly, some pop-ups can be too, well, popperly. Great paper engineering is attention-grabbing, but a good text needs to accompany it.

Robert Sabuda and Matthew Reinhart's Encyclopedia Prehistorica: Dinosaurs gives us a fine example of solid text combined with stunning illustrations. Full-page pop-ups include perennial favorites such as ankylosaurus, triceratops, and brachiosaurus, all displayed in vivid colored papers. But supporting these eye-catching visuals is a clear, engaging, and informative text. The explanation of the demise of the dinosaurs, for example, poses a thought- provoking question: "Around 65 million years ago, dinosaurs, along with their relatives, the flying pterosaurs and marine reptiles, abruptly and mysteriously vanished from the earth. Paleontologists have searched for an answer but don't all agree. Small animals like mammals, insects, and modern reptiles survived, so why didn't the dinosaurs?" In the pop-up world version of sidebars, text is often expanded through extra flaps, but in this case, the discussion is contained in a five-page mini-book (complete with two centerfold pop-ups) that briefly details three possibilities: asteroid implosion, disease, and climate change. There's enough information to satisfy the mildly curious and enough substance for further research if the reader is so inclined.

Such added flaps, pull-tabs, and various other paper mechanics not only enhance the interactivity of pop-up books but also account for much of their popularity. What these features do is give children the drama of the page-turn on steroids. Youngsters can control how fast or slow a dinosaur or crocodile (Predators by Lucio and Meera Santoro) will pop up. Additionally, they can control their reading experience every time they return to the book; they decide their own level of inquiry by choosing either to explore the side avenues offered by interactive features or to ignore them. Making those kinds of decisions is what reading is all about: it's the way sophisticated readers approach a book, knowing that they have the power to read everything, something, or nothing at all. But these behaviors aren't automatic; they're learned. Pop-up books are but one tool to demonstrate that process.

I saw the power of this interactivity recently at The Wizards of Pop exhibit at the National Center for Children's Illustrated Literature (NCCIL) in Abilene, Texas. Showcasing the work of Robert Sabuda and Matthew Reinhart, this exhibit included a large free-standing paper-engineered scene of the dinosaur world intended to draw attention to the pop-up book Encyclopedia Prehistorica: Dinosaurs. With a similar purpose, there was also a huge, wall-mounted tiger from Reinhart's Jungle Book. Since size really does matter with young audiences, I expected lots of kids to congregate around these two figures. They didn't. While these impressive sculptures did draw youngsters into the exhibit, the children quickly moved on to the actual pop-up books on display. They would page through these books to see how the pieces of an illustration went together, compare a mock-up to the real deal, or get an idea of what was contained inside the covers. They didn't just want to see these marvels; they wanted to make them happen.

Of course, the elephant in this literary room is permanence. Do pop-up books withstand being pulled and pushed and opened and closed? Several years ago, for her master's thesis at Texas Woman's University, Wanda Meador set out to answer that question. She purchased a number of pop-up books and circulated them in her elementary school library. Her conclusion was that while pop-up books didn't last as long as traditional books — they lasted about six weeks to six months — they circulated far more often in that short period of time than did their traditional counterparts. Surprisingly, the number of circulations before a book had to be discarded because of use was about the same with both pop-up books and traditional books.

Meador discovered that flaps last longer than any other part in movable books, and those pop-ups protected by flaps showed relatively little wear. Pull-tabs were the most fragile elements in the books she circulated, although the pull-tabs in sturdy books for the very young (Maisy Bakes a Cake by Lucy Cousins, for example) held up quite well. Poorly executed pop-ups, or those designs that don't quite pop all the way up and look like picket fences supported by boards at a forty-five degree angle (such as the scenes of fruit in The Very Hungry Caterpillar Pop-up Book) were the most vulnerable of the centerfolds. But those great centerpiece spreads that pop up as well as fold down without any reader manipulation (such as the final scene in that same book, of the "beautiful butterfly") held up nicely.

With this information in mind, the 2006-2007 Texas Bluebonnet Award Committee placed Robert Sabuda and Matthew Reinhart's Encyclopedia Prehistorica: Dinosaurs on its annual state reading list. This was the first time a pop-up book had been so honored. Librarians reported that it wasn't the handling of the book that caused trouble but the transporting of it from library to home. Consequently a number of librarians purchased heavy plastic envelopes and circulated the book with this added protection. They also requested that youngsters not place the book in the book drop when returning it, but instead bring it to the circulation desk. Yes, many copies were damaged, but so were many copies of other books on the list. But what Encyclopedia Prehistorica: Dinosaurs did was immediately show over 200,000 readers that this list was, in their minds, a cool one. One librarian surprised me early in the process when she said that the children (in grades 3-6) in her library figured that any book on a list that contained Dinosaurs must be worth looking at, so they went directly from Dinosaurs to other books on the list such as The Lightning Thief. Dinosaurs didn't win the balloting that year, but it certainly pleased many a young reader.

That pleasure is what will hold up long after the paper engineering wears out. And, of course, it should wear out. To treat pop-up books — or any children's books, for that matter — like Madame Alexander dolls, collectors' items to be handled gingerly with the daintiest of hands, is to miss the point of their existence. Books are made for reading, for being loved, for returning to time and time again. Like dolls that have been played with so many times their arms are askew, their faces are grimy, and their hair is matted, well-loved books display their wear and tear as badges of honor.

Good Pop-ups

Marion Bataille, illustrator ABC 3D (Roaring Brook, 2008)

David A. Carter Yellow Square; illus. by the author (Little Simon, 2008)

Heather Couper and David Pelham The Universe; illus. by the authors (Random, 1985)

Jonathan Miller and David Pelham The Facts of Life; illus. by Harry Willock (Viking, 1984)

Jonathan Miller and David Pelham The Human Body; illus. by the authors (Viking, 1983)

Matthew Reinhart, reteller The Jungle Book; illus. by the reteller (Little Simon, 2006)

Robert Sabuda, reteller The Wonderful Wizard of Oz; illus. by the reteller (Little Simon, 2000)

Robert Sabuda and Matthew Reinhart Encyclopedia Prehistorica: Dinosaurs; illus. by the authors (Candlewick, 2005)

Lucio and Meera Santoro Predators; illus. by the authors (Little Simon, 2008)

Ron van der Meer and Alan McGowan Sailing Ships; illus. by Borje Svensson (Viking, 1984)

From the November/December 2009 issue of The Horn Book Magazine.