I decided to use Autodesk Fusion 360 as my main CAD tool for this semester. It has a free multi-year license for college students, and it's one of the industry standard tools. It's capabilities include parametric design, and both 2D and 3D modeling.
For my final project, which is supposed to incorporate everything that we will learn this semester, from electronics to machining, I'm tentatively planning to build a quadcopter. I'll have to do machining to make the body of the drone, some circuit work to make the motors, and learn communications/networking in order to control the quadcopter using radio signals. It's a challenging project, but it's been done for this class before.
As a primary resource for this project, I'm using this website: http://beginnerflyer.com/build-a-drone. The dimensions of my frame are going to be 50cm X 50 cm, which is in the middle range of typical drone sizes.
I'll continue to update this page as my drone design progresses.