Dear Hannah - I'm a #StandupStoryteller. I'm the "Brother From Another Planet". Strange people think I am strange. I think that what I experience is strange. And still I rise. I just completed another school year. I am trying to see where I have been ... and where I am going. I accept that "mental math", critical thinking, and problem solving skills are in rapid decline in our society ... amongst young people and adults. I focus a lot of my energy on countering that trend. You don't have to like math, but ... you must get your money right. When we study exponential functions, it provides an opportunity to introduce one of my "mental money math" favorites ... "The Rule of 72". The "Rule of 72" says that you can estimate the number of years it takes an investment's future value to "double" by dividing 72 by its interest rate (rate of return) ...