The monopoly of textbook companies

Now that I am retired I am thinking about publishing a full series of interactive high school math textbooks that are aligned to the new core curriculum standards.  As the primary author of one of the exemplary curricula I am thinking that doing them as interactive pdfs that can be printed or delivered as digital content and making them free or for small fee to schools, teachers and anyone else who might be interested. For too long the major textbook publishers have controlled the content that teachers deliver in their classrooms. Given that digital access is becoming less of an equity issue and that if all content was digital, schools would not need to purchase, warehouse and replace expensive texts. Consequently, providing every student with a laptop, netbook or tablet is less of a problem. An  iPad, net book or laptop can be purchased for less than the five to seven textbooks at $75 or more that a student needs every school year.