This week, we will have a little look at the scale of the Solar System:
Either, you can choose objects (which are spheres) to represent the different planets. Here are the size of the diameters of the planets.
Earth->12,756km Mars-> 6,792km
Jupiter-> 138,346km Saturn->120,536km
Or if it's easier you can fill out this sheet which will help you Mathematically scale the planets of the Solar System.