You all have different skills and experience with using iMovie. After creating your research plan, think about what you want to learn and do some inquiry into iMovie. Below is a playlist I have put together of good tutorials, but you are not limited to these resources.
Link to playlist here.
Also, make sure you play with iMovie to practice and learn these skills. You won’t learn by just watching the video and not trying to create something in iMovie. The more you play, the better you’ll get at movie making!