Being a great science teacher is not so different from being a great science writer. You have to convince your audience to pay attention to you, rather than to the myriad other potential sources of entertainment and engagement out there. You have to maintain their attention: at any time, a reader can click over to a different website or turn the page of the magazine or newspaper. You have to break down complex ideas into understandable chunks.
The writer is making an unstated contract with the reader. The writer says to the reader: I will value you and your time, because I know that you are just two boring sentences away from reaching for your cell phone and playing Angry Birds, and in return you will spend some amount of time reading my sentences, equal to only a small fraction of the time that I spent crafting those sentences in the first place.
As yet another semester winds down, I realize there are many things I've learned from being a science writer that transfer extremely well to teaching. Here are three of them: (1) a student is a complete person, and the class he or she is taking is but one part of his or her life; (2) if I am not excited about something, I can not hope to excite a student about something; and (3) no matter how exciting something is, it needs to be accessible.