How do you convince a student that on Dec 22, the Sun shines on the Tropic of Capricorn, especially when your school is at 50N? The daily motion of the Sun is easy to show, what about the annual motion? What you can see with difficulty is the north-south movement, not the precise location of the sub-solar point, the precise point on the Earth's surface where the Sun is exactly overhead.
Our model helps you to do exactly that. It is customised to your location and once oriented properly, shows you exactly where the Sub-solar point is. So, no matter where you are on Earth, the shadow cast by the model hairlines will be exactly on the Equator on the equinoxes.
For ordering, please specify the exact latitude and longitude of your location. I will send you by email a pdf file which you can print and assemble to make your own model!