I'm teaching middle schoolers timberframing in a one hour class that meets Twice a week. We are currently in the middle of laying out and cutting timbers for a 16 foot long covered bridge. Hopefully it will be raised this fall. I want them to understand more of the history/ tradition and design aspects of the craft. In fact, I would like them to design the next project, probably a small two bent shed/barn. I am looking for any info about books and videos that can engage this age learner about the craft in general and how to design and draw that isn't too technical. Thanks!