Screencast-o-matic

Screencast-o-matic is a good source to teach students. It's different than normal teaching because it's a lot like a podcast but they get to see a slide show during the podcast. You can make a slide show then you record yourself talking and teach the students with your slide show, You have the option to let them see you or just hear your voice. So this would be good to use in a flipped classroom.