Last weekend I went to a technology workshop and learned about this free site.
https://www.playposit.com
this is a free site, very easy to learn, it can turn your educational video into an interactive learning video by setting the pause and insert the questions for the viewers to answer before moving forward to the video. The learning can rewind but cannot forward without answering the questions. The questions could be made into multiple choices and the program will grade it automatically, or a simple assay questions. You can also pause the screen, and add your explaination in written or audio.
I love to use this site to expand my classroom and engage the students self learning at home. But if you are teaching other subjects, you can also use this to interact with your students as well.
I recommend that you check out this site.