This Spanish Easy Review vocabulary quiz takes a look at the Earth's structure. Okay, so you are probably thinking that you already have a science class and now this makes two. You can relax on that front because what this quiz will focus on is the Spanish vocabulary of science words. It will also complement your normal science class on learning about the Earth’s structure. As you may recall, the Earth has six layers. Those layers include the inner core, outer core, lower mantle, upper mantle, lithosphere and crust.