Free. Open-source. Peer-reviewed.
A solution to the high cost of senior course textbooks? Some of these may be a perfect fit for Grade 12 level high school courses
"Our textbooks are professionally produced but come with a nonprofessional price tag: $0.00. That's right, online editions are free, and printed copies just cover our costs to produce them. ...Take a look at one of our textbooks. Download the full version, for free, forever. If you like what you see, let your friends know how they, too, can get a great textbook for an unheard-of price."
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