This involves the exploration of physical observables, often in relation to motion, energy, and electricity. Students gain an understanding of fundamental concepts such as length, time, mass and temperature through appropriate experiments. This allows them to develop simultaneously a sense of scaling and proportional reasoning, to recognise the need for common units, and to select and use appropriate measuring equipment. Exploring concepts such as area, density, current, and energy helps students develop the ability to identify and measure a range of physical observables, and through experimenting, to investigate patterns and relationships between them. Students also design and build simple electronic circuits. Students develop an understanding of the concept of energy and how it is transformed from one form to another without loss. They also research sustainability issues that arise from modern physics and technologies, and our generation and consumption of electricity.