Below is an additional comment about e-textbooks.  It was posted to PHYS-L by James Deane, who teaches at the Ottawa, Kansas high school.  Jim gave me permission to share his comments. 

 “I have collected several online textbooks to ‘give’ to my students
over the years, but they are all free.  Some are better for high
school students, some better for college, some better for teachers.

I haven’t used any of them as a primary text, but then I have
plentiful decent textbooks

Motion Mountain:
Light and Matter:
Discover Physics:
Newtonian Physics:
Physics Hypertextbook:
Spiral Physics:
Stargazers to Starships:


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James K. Deane
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