Libraries, she said, "are community chests, loaded with a wealth of information available to everyone, equally."
The event launched "The Campaign for America's Libraries," a five year nationwide effort to teach about libraries and promote their use.
"Libraries are well loved, but they're not as understood as we would like," said Nancy Kranich, president of the American Library Association.
"Mrs. Bush is the 'first librarian' of our country," she said. "I think she represents a very important opportunity for us to have this very visible way of saying reading is important, books are important."
In an article in Tuesday's Washington Post promoting National Library Week, the First Lady wrote that, "libraries have been called 'Palaces of the People.' Never has it been so true: Today libraries are palaces of all the people. The key to those palaces (and the treasures within) is a library card."
"I loved being surrounded by volumes of literature and tomes of information. Knowing that the cure for many a curiosity was an arm's length away was both satisfying and empowering," she added.
Mrs. Bush had some advice for parents and involved adults in her article. "Children benefit greatly from reading activities starting at a very young age. Parents should read to their children early and often, and once children learn to read, they must practice reading every day."
Speaking to a group of children and adults at Washington's Northeast Neighborhood library she said, "Our nation runs on the fuel of information and imagination that our libraries provide every day."
She and Baltimore Orioles shortstop Mike Bordick read I Took My Frog to the Library, a story about a girl who learns she is welcome at the library but her pets must stay home.
Pausing to show the pictures in the book, Mrs. Bush asked the children questions as she read the story. She explained that a python is a "big, big snake," and laughed when one youngster asked if she would read the book again.
"It's pretty fun, but guess what you can do? Check it out at your library," Mrs. Bush replied.
As a result of her efforts promoting reading and libraries, Mrs. Bush, who received her first library card in Texas "at a very young age," was awarded her own Washington public library card.
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