Not everyone has the will or patience to draw very delicately, but that doesn’t matter. Also look at how beautifully the tails disappear into the snake’s jaws.
Suggestion for teachers: leave room for everyone’s own interpretation of this exercise. Some pupils very patiently draw a refined structure, others prefer to add other figures, fantasizing about a situation or story.
Extra: Draw a tail-eater wriggling around itself. Parts of the snake’s body now overlap each other. The snake could only untangle by letting go of its tail. Decorate your wriggling tail-eater with just color or again with surface structures.