Blended learning has three components: First, using blended instruction, teachers replace their lectures with self-made instructional videos. This frees up teachers’ class time to work directly with students by eliminating the lecture bottleneck, which makes possible the second component of the model: self-paced structures that empower students to learn at their own pace within each unit of study, either individually or in collaboration with peers. Finally, teachers use mastery-based assessment to ensure that all students are truly understanding the content and skills they need to be successful.