provides direct free downloads of thousands of free ebooks originally from Project Gutenberg. Although Overdrive is generally for use with a library membership, these are direct free downloads in EPUB.
has over 250 free ebooks for free reading online in a flash player. Age range is from 3 to 11. Audio and associated activites are also available for most, if not all, the free ebooks. Thanks to Katharine for this nice link.
Free eBook Index
has links to 375 free ebooks offered in Kindle format (as well as other formats). Most of these are classics, but there is a decent collection of Philip K Dick and a couple of other more recent works.
monitors Amazon for free ebooks for children and post a few per day at the site and also links to a larger listing of free offerings via lists maintained by , the site owner, at Amazon's Listmania. Updates available by RSS and email.