While standard e-books from publishers are great, not all are appropriate for the classroom. Here are some resources that do fit in schools:
Flexbooks (www.ck12.org) offers extensive titles in math and science that are customizable, easy to update, and free.
Classic Books Online (www.classicsarchive.com) has about 1,600 books available in either HTML or PDF format.
Curriki.org has 150,000 members that share curriculum ideas, resources, and knowledge.
Kinetic books (www.kinetic books.com) offers math and science books via CD , Web download, and Web access.
MIT (ocw.mit.edu/high-school) has free online courseware available in math, science, and the humanities.
Planet eBook (www.planetebook.com) has classic literature available as a free download.
Project Gutenberg (www.gutenberg.org) has more than 33,000 titles available in many languages.
Flat World Books (www.flatworldknowledge.com) provides study tools, like flash cards and practice quizzes.