Here is a helpful app to help teachers create green screen videos — from educatorstechnology.com
Excerpt:
If you are looking for a good green screen app to use in your teaching and with your students in class, Do Ink is definitely one of the first options you should consider. Green Screen by Do Ink allows you to easily create beautiful videos and visual presentations incorporating a wide variety of multimedia materials. As a teacher, you can use it to design tutorials, step-by-step guides, explainers, visual illustrations, presentations, posters, and many more.