My students and parents LOVE this lesson. I do this one with First Grade. This year, I did the lesson with Grade 1 and the Grade 1 and Grade 2 Combo classes.
I think it always turns out great. The nice thing about this is if they make a mark they do not like, they can just color over it and it becomes a bigger boat or another sail. It also reinforces how to draw basic shapes.
This year, I had extra wide sharpies which made it easier for my students to color in large sails or large boats.
I think one key to success is to make sure the students go slowly around the outside and then they can move quickly when they are in the middle of the image.