This paper presents an educational system for improving the understanding of the students through the use of Web3D and AR presentation scenarios. An engineering and design application has been experimentally designed to support the teaching of mechanical engineering concepts such as machines, vehicles, platonic solids and tools. Note that more emphasis has been given to the visualisation of 3D objects because 3D immediately enhances the process of learning. For example, a teacher can explain what a camshaft is using diagrams, pictures and text, etc. But it still may be difficult for a student to understand what a camshaft does. In our Web3D system pictures, text and 3D model (which could be animated) can be visualised so that the student can manipulate and interact with the camshaft, and also see other related components such as the tappets, follower, etc. arranged as they might be with an engine (Figure 4).