When the first missionaries went out to Africa, the UK used a different system to measure money, made up of farthings, pennies, pounds and guineas. we have only counted money the way we do now (100 pennies in a pound) since 1971.
Why not have a go at designing your own money? What would it be made from? What shape would it be? What picture might you put on it? What would your units of currency be called and how much would they be worth? What symbol would you use to represent it?