If you use Screencastify for recording instructional videos you know how valuable of a tool it is. A nice feature that is relatively new is the ability to add Interactive Questions into your video.
To add the questions you will simply need to access your previously created video and go into your recordings. Make sure to select he interactive questions icon on the right and then you can then start watching your video. When you are ready to ask a multiple choice question make sure to click on the blue "Add Question" icon at the bottom of the page (has a time stamp). Make sure to add at least two possible answers and choose the correct answer. Continue on with as many questions as needed and then share your video with others (top of screen). You can share directly to Google Classroom or as a link.
Once the quiz has been completed you will see responses at the top of the screen as well with the quiz already graded.
If for some reason you need to adjust your questions, make sure you click on list view on the right side of the screen.
Embedded below is a 2 minute and 57 second YouTube tutorial.