Knowmia is a web site for teachers where they can upload their videos so that the students are able to access them.
Ariel Braunstein and Scott Kabat developed this web site so that teachers could share experiences and resources with each other.
There are some great case studies with interviews with teachers who are successfully using these videos in their classrooms.
There is a large database of videos that teachers can access and use with their students.
For those using a flipped classroom approach with their students Knowmia has, coming soon, a simple home assignment tool. For each assignment you will be able to include a series of lessons that you create or find in their ever growing lesson database. Homework may include three types of assessments: multiple choice questions, open-ended questions, and textbook questions (questions from textbooks that your students already use). Once you send out an assignment, you will be able to keep track of your students' actions and performance: When did they open the assignment? How did they answer each question? Which concepts require additional help and/or practice? Although the actions of your students are completely private and secure (visible only to you), the homework itself is shared instantly with other teachers so they can learn from you and borrow any portions of it for their own students. You may opt to do likewise with their assignments and lessons.