Look at these pictures below:
What do you notice about the way the shapes are stacked?
Are they stacked on their flat faces or curved faces?
Which balance best do you think?
Can you see any shapes that are stacked on their curved faces?
Are these on the top or the bottom of the model?
Why do you think this is?
If you have some building bricks like this have a go at building some towers and explore what happens if you stack with curved faces!