It’s useful to incorporate SketchUp in a manual drafting class, because it’s a good tool for those who have trouble visualizing 2D/3D relationships. They can draft their 2D views on paper and then model them in SketchUp to see if they work.
Drafting, Modeling and 3D Printing with Lydia Sloan Cline
Hand drafting for Interior Design, SketchUp, Autodesk 123D and MakerBot