The main point of this example is about "observing," one of the most valued skills in science. Observation is usually emphasized beginning in the Upper Elementary grades. But it is often easier to observe than to explain. "How curved mirrors actually work" is sometimes covered in High School physics. The principles are also discussed in most encyclopedias, under "Mirrors" or "Optics," and are mentioned with respect to lighthouses, telescopes, and amusement park activities. (One benefit of making observations, or even memorizing "facts," for which you have no deeper understanding at the time, is that sometimes, perhaps many years later, you may suddenly realize what they mean or why they are important.)