The best learning in Mathematics comes when we revisit earlier work to reinforce new concepts – that is, a spiralling curriculum; somewhat like this unusual cloud effect. For example, we learn our times-tables and later apply this knowledge to solving equations; then we apply our knowledge of equations to calculus, etc. So, we are always revisiting our earlier work but at a higher level as we progress through each year level. Like a tradesman, we use our simpler tools to help us handle more complex problems. That is what is great about Mathematics – even the work we did in elementary is useful in high school. Check out some more unusual cloud shapes by clicking on the pic below;