I begin by showing MANY examples. At first, they couldn't figure out how each author had started but I had one student who piped right up with, "They all begin with a question!"
I've included a list for each type of lead I introduce at TpT (Kick of to Beginning Writing).
Then the kids practiced, practiced, practiced. We began in their narrative section of their notebooks and they were given Post-Its and "teacher" pens (which makes writing so much more fun)!!
Once we shared, we looked at our informational books and found question leads. The kids went to their informational section and began practicing.
Here are a few examples.