Riddle: What's black and white and read not nearly as much each summer as parents, teachers and librarians all over Prince George's County would like?

The answer? Books.

So to encourage children to read, the Prince George's County Memorial Library System is sponsoring a variety of programs for children from preschool through high school that offer incentives and fun activities to draw them into local libraries.

Library officials said they are inviting 'tweens and teens to "electrify those long summer days!" by participating in "Read Electric," a program that links reading popular books to watching films based on the same novels. Children ages 12 to 18 are encouraged to read a selected group of books, then attend showings of films based on those books at library branches. Children will register for the program at local libraries, then keep a log of the books they read. Those who read at least four books by Aug. 15 will receive a small prize and become eligible to win a gift certificate to a store of their choice.

The book and film pairings include "Holes," by Louis Sachar; "Seabiscuit," by Laura Hillenbrand; and "The Whale Rider" by Maori writer Witi Ihimaera. The films will be shown at libraries on a rotating basis between June 30 and Aug. 4. Admission is free.

" 'Read Electric' was kind of our hope to get some kids in who otherwise might not come in to the library and who are not active readers," said Bridget Warren, the library system's chief of public relations and programming. "As kids grow, they want things to be social occasions, too. They can read the book before they come in, see the film with a friend and hopefully stay for a brief talk with the librarian, where they'll discuss plot differences between the book and film, whether a minor character in the book is more prominent in the film and . . . characters and episodes from the book that are entirely left out. We want them to see the library as a place where they'll have fun and hopefully . . . they'll come back for another program later."

Library officials also want the children to learn about analyzing characters and plot and other aspects of critical thinking, Warren said.

For children ages 6 to 12, the libraries are operating a program called "Readers Rule!," which centers around common fairy tales and folk tales from different countries, including Sri Lanka and Tibet and countries in South America. Children will participate in a variety of activities, including reading books, magazines, newspaper articles and poems. They will keep track of their work in an activity log.

Children who register at library branches will receive a ticket to a Bowie Baysox baseball game. As they read more books, they will receive a coupon for a free book from one of the library system's used book stores or a free video or DVD rental. When they complete the program, they will receive a free paperback book from Barnes & Noble, Warren said.

"Reading Royalty," for preschoolers and kindergartners, offers the same incentives for children who read with their parents or a caregiver.

The summer reading programs will be kicked off with several activities in the next two weeks. Beltsville Friends of the Library is starting its reading program with an ice cream social for all ages at 7:30 p.m. June 15 at the library, at 4319 Sellman Rd. The Bowie Branch, at 15210 Annapolis Rd., is kicking off its summer programs with a presentation of "Unlucky Cinderella" by the Bowie Troupers at 2 p.m. on June 14; 7 p.m. on June 15; and 3:30 p.m. on June 16. The Spauldings Branch, at 5811 Old Silver Hill Rd. in District Heights, is sponsoring "Once Upon a Book," at 1 p.m. June 22 for children ages 6 to 12.

Warren said parents should encourage all children to read over the summer. Studies link academic success to reading. As children get older, the Internet, video games and other diversions compete with time they may have spent reading when they were younger.

"Children who are 6 to 12 still come in [to libraries] with their parents, but as they get older, kids resist doing anything with their parents," she said. "But as kids grow up, the books they choose can actually help them navigate their own lives. They can learn a lot about the transitions that kids experience at that age by reading and understanding that adolescence is a universal experience, the problems they will encounter and that they will survive. There are books and novels that address these issues."

Warren said parents should give children freedom to choose their own books. Fantasy, coming-of-age stories, biographies and even comic books are encouraged by librarians, she said.

"There are so many things for kids to read that we didn't have," Warren said. "There are graphic novels, illustrated novels where stories are told just as much through visual images on the page as through the text. Some people look at that and think, 'That is a comic book.' But they're not. They are a wonderful thing for children who are reluctant readers or visual learners. Everyone has those ways that they learn best."

Warren also cited audiobooks as a way to help children with dyslexia or other conditions that make them reluctant to read.

"As long as they are reading," she said. "That's the goal."

The libraries are also sponsoring "Escape to Reading," which offers adults the opportunity to enter a drawing for a grand prize by reading six books by Aug. 5.

For more information, visit your local branch, call 301-699-3500 or check the library systems' Web site at www.pgcmls.info.