The children pour water into the clay bins, as the teacher describes each form. This lesson directly teaches the land and water forms, indirectly refines hand/eye coordination and prepares the student for future study of physical geography.
You can see in the above photo, I've extended the lesson with a coloring sheet. Each pair of forms (island/lake, peninsula/gulf...) is on the shelf next to a basket of these sheets. The children can draw and color in the forms if they choose. Another extension is to locate these forms on the puzzle maps.