Up until lesson 5, I've been very adamant drawing everything freehand, with felt tip pens, and so on. And this has been for a good reason - it's important to maintain a certain degree of the right kinds of challenges to ensure that you guys gain as much as you can from each lesson.
This lesson, however, is going to be a little different. I am allowing, and in fact encouraging the use of the following:
Ballpoint pen for your linework (don't switch pens to do any sort of "clean-up" pass - use the same pen through all your lines, including construction/box subdivision/etc)
Brush pens for filling in large areas with solid black
Rulers/straight edges for drawing precise construction lines
Ellipse guides for constructing and aligning your ellipses
French curves for any complex, curving lines
Whenever drawing freehand, I still want you to apply the methodology I've outlined in the past - the ghosting method, drawing through ellipses, and so on. That said, in this case it is inevitable that with all of the necessary construction lines, and the significance placed on precision, it's important for you to be able to use tools that will allow you to focus more on the meat of the lesson, which is really about the manipulation and construction of complex compound forms.
As before, do not use pencil or digital media.