Primary 6 have been learning about the properties of different materials in the Science class. They conducted an experiment  to make density columns to see that different fluids have different densities. They poured a layer of treacle, then water, then oil into a beaker.  These layers remained separate on top of each other and even after being stirred, they settled back into 3 layers with the most dense liquid at the bottom and the least dense on top. They then added small classroom objects to the beaker and noted how far they sank as an indication of their density. Metal objects were most dense and sank straight to the bottom of the beaker while light plastic objects stayed in the top layer.