Space telescopes are some of the most precise and complicated machines ever built. Not only must they survive the harshness of space travel, but they also need to be incredibly accurate: misalignments by fractions of a millimetre can have huge effects on the quality of the images they capture. In 1990, the Hubble Space Telescope became the first "large" telescope launched into space, and it immediately changed our view of the entire universe. However, in that time imaging technology has come a long way, and with Hubble's on-board cameras degrading because of cosmic radiation, it is time for a replacement. Enter the James Webb Space Telescope, or Webb for short. Webb offers a myriad of improvements over Hubble and is also tuned slightly differently in order to build on the discoveries Hubble made. The authors bring some of the physics behind the recently launched James Webb Space Telescope to the primary classroom.