A central aim of Waldorf Education is to stimulate the healthy development of the child's own imagination. Electronic media hamper the development of imagination, and the content is often not age-suitable. Waldorf teachers work with parents to explain the connection between media and learning, and respectfully ask students to adhere to media guidelines. Also, the rich classroom content, stressing creativity and imagination, works to dampen enthusiasm for imagination-replacing media.
There is more and more research to substantiate these concerns. See:
• Endangered Minds: Why Our Children Don't Think by Jane Healy
• Failure To Connect: How Computers Affect Our Children's Minds For Better and Worse by Jane Healy
• Four Arguments for the Elimination of Television by Jerry Mander
• The Plug-In Drug by Marie Winn
• Evolution's End: Claiming The Potential of Our Intelligence by Joseph Chilton Pearce.