We use sketchbooks on a regular basis in the art room. Picture planning, drawing from observation, and recording information in our sketchbooks helps students understand that pre planning and practice are a large part of being an artist.
Sketchbook prompts are given when students complete lesson work and as homework assignments from time to time.
I just began using prompts so my list is growing. As soon as I can figure out how to link my list I'll have it here :)