This course was made to help a pretty specific audience; people who need to recognize farm buildings by structural components. It turns out that it is pretty hard to show the idea of structural components, especially when you don't have any pictures to show what they heck you are talking about. So I decided to make re-usable illustrations of each component, then have the learners "build" each barn type so they could see the different parts. After that information is introduced, we talk about some modifications that still apply. Fun course!