Hi Rachel, thanks for sharing this project. This is very exciting. I would look at the initial inquiry planning form to guide you to the questions you might first need to ask the teacher. It really is best if they can tell you what their learning objectives are for their students.
I would narrow the options they can choose from down a little as they will need to spend too much time reading all of it to decide what they would like to focus on. Two or three choices at the most.
I am sure that there are others who can think of some better questions than me but here are my suggestions to get the discussion going. You need to think about putting the students into the heart of the research so questions like…
Would you have to be a bad person to make a good pirate?
What would your life be like if you were a pirate?
Which you would prefer to be and why? A corsair, privateer, buccaneer or a pirate?
I hope this helps.