TED, the franchise behind the insanely popular TED Talks series, has its own flipped learning platform, TED-Ed. On this site, users can build lessons around any TED Talk or YouTube video. You can write multiple-choice questions—with feedback after a student answers and video hints that will replay just the section of video with content related to that question—and open-ended questions that allow students to respond however they choose. The Dig Deeper option lets you add explanatory text with links to other resources on the topic. And the Discuss feature opens up the floor for discussion among all class participants.
You can also borrow one of the TED-Ed Originals, lessons created collaboratively by educators and professional animators.