CK-12 is a great platform that provides high quality curated STEM content for teachers and students. Its library has over 5000 math and science materials ideal to use in class. Flexbook is one of the best features I like in CK-12. Flexbook provides a wide variety of free textbooks for teachers to use in their lessons. It even allows teachers to create their own Flexbooks using materials from other textbooks in the site. Textbooks are available in multiple formats including: PDF format, Kindle and Nook and iPad.
The great thing about Ck-12 is that it provides teachers with a handy tool that they can use to create their own multimedia textbooks. The video below from Gladys Scott walks you through the process of how to create a multimedia textbook using Flexbook functionality.
