Harve has been very interested in size so he built with his knobless cylinders which he then measured. After that he was asking about the size of buildings so his mum and he Googled London buildings and printed off a size graph. He then wanted to know the tallest building in the world, so we added Burj Khalifa and then he wanted to add the biggest dinosaur the Brachiosaurus and then of course fire engine police care and ambulance. He then wrote all the names . What a wonderful project.