aka: Golden Mean, Golden Section, Divine Ratio; Fibonacci Sequence
Fabulous Fibonacci and his Nifty Numbers - another great lesson plan from the Mensa Foundation. Designed for 4th graders to be able to do alone (or usable either higher or lower with a teacher), this lesson plan is comprehensive, correlates with the Common Core, and is free!
da Vinci's 'Divine Proportion' Model Series - his is a series of 5 structural forms based on Leonardo da Vinci’s sketches in the De Divinia Proportione (The Divine Proportion). Representing fire, water, air and heavenly ether, each handmade wooden model features intricate hand crafted joints and are finished in a translucent shade of distressed French finish honey.