Explaining what an urban model is

This is a starter that I use to explain what an urban model is. I make a paper aeroplane and ask the pupils to tell me what it is. They all call out that it is a paper aeroplane. I then ask them what are the differences between the paper aeroplane and a real aeroplane. They come up with a huge number of differences on size, scale, features etc. So I then say to them that it is interesting that despite all the differences they still all recognised it was a plane. I then tell them it is a model - a smaller, simpler version of what it represents, exactly the same as an urban land use model.