In Stage 2 Science, students have been learning about the states of matter and how melting and freezing can be used to make things. Recently, students applied their learning to design their own chocolate shapes. They made a model of their chocolate shape using Plasticine. Their Plasticine models were then used to make a hollow plastic mould that can then be filled with melted chocolate or other liquids to be frozen.
The process of making the plastic moulds is called 'vacuum forming' or 'thermoforming'. A sheet of non-toxic thermoplastic is heated in an oven until soft. The soft plastic sheet is then lowered over the Plasticine model and sucked into place using suction from a vacuum cleaner. The plastic sheet forms closely around the Plasticine model creating a hollow shell of the object. You can find out more about the process by performing a Google search!