Visualising solid shapes

We,8th graders at Isai Ambalam school children started a lesson called visualising solid shapes in mathematics. We used sodo cubes to understand different views of  a solid shape.  Children have been divided into four groups. 20 sodo cubes were given to each group. One child from each group should make a solid shape using 20 cubes and should draw the front view, side view and top view. He has to show this views to his partner without showing the shape.The other person should make the same model by seeing drawings. Children enjoyed this activity. They were able to draw the different views of solid shapes and also make the shapes by seeing the views. But the question they had was how to draw the views if the model has holes. Then they came to the conclusion of using dotted lines to represent the holes.