Teaching models that focus on blended and virtual learning have become important during the past year and have become integral for the continuance of learning. The i²Flex classroom model, a variation of blended learning, allows non-interactive teaching activities to take place without teachers' direct involvement, freeing up time for more meaningful teacher-student and student-student interactions. There is evidence that i²Flex leads to increased student engagement and motivation as well as better exploitation of teachers' and classroom time leading to the development of higher order cognitive skills as well as study skills for students' future needs related to citizenship, college, and careers. The Handbook of Research on K-12 Blended and Virtual Learning Through the i²Flex Classroom Model focuses not only on how to design, deliver, and evaluate courses, but also on how to assess teacher performance in a blended i2Flex way at the K12 level. The book will discuss the implementation of the i²Flex (isquareFlex), a non-traditional learning methodology, which integrates internet-based delivery of content and instruction with faculty-guided, student-independent learning in combination with face-to-face classroom instruction aiming at developing higher order cognitive skills within a flexible learning design framework. While highlighting new methods for improving the classroom and learning experience in addition to preparing students for higher education and careers, this publication is an essential reference source for pre-service and in-service teachers, researchers, administrators, educational technology developers, and students interested in how the i2Flex model was implemented in classrooms and the effects of this learning model.