What do you think about this for the hovercraft presentation? You can make a 3 fold poster, or you could make an online project on Tackk. If you want to try it, just erase my words and put in your own.
You can also add photos of hovercrafts, photos of you making a hovercraft or a video, or a youtube of those girls making their cool hovercraft life size.
You don't need to use Tackk. It's just another idea.
What are the steps in the engineering design process? You could use those as your major headings.