At the end of class, we tried a blind contour portrait - still using the slow, smooth line, but not looking at the drawing at all, only at the subject, in this case a classmate model. This was lots of fun and I bet most of them went home and practiced on siblings!
Contour drawing is a great way to begin a longer, more involved artwork. If you'd like to try this in your classroom, check out my Observation Drawing packet, available on Teachers pay Teachers. I have also just added a free download for the foil figure sculpture, which goes so well with this unit. https://www.teacherspayteachers.com/Product/Observational-Drawing-Gesture-and-Contour-exercises-2656125