That's ideal. What we need is enough schools and teachers with an incentive to contribute to a public domain textbook system. Each contributor should write a g

That's ideal. What we need is enough schools and teachers with an incentive to contribute to a public domain textbook system. Each contributor should write a good presentation of a specialty or a favorite subject. Then the whole book will be among the best textbooks possible. And the textbook cartel will collapse in the USA and the less developed world while students have better books for free.