The Maya are known for their excellent understanding of mathematics. They developed their own number system, using dots (for the number 1), bars (for the number 5) and shells (for 0), rather than the digits 0-9 we would recognise today. They were also possibly the first civilisation to use zero as a place holder. Our numbering system – the decimal system – uses ‘base 10’. We have ten digits: 0-9. Each time we move up a place value, we multiply the previous place value by 10. This is why we have ones, tens (1x10), hundreds (10x10), thousands (100x10) etc. The Maya used a ‘base 20’ system called the ‘vigesimal system’. They had 20 ‘digits’ (each made up of a combination of dots, bars and shells): 0-19. Each time they moved up a place value, they multiplied the previous place value by 20. They began with the ones, then the 20s (1x20), then the 400s (20x20), then the 8000s (400x20) etc. So while we just use our fingers to help us count, the Maya had to use their toes too! Twitter: @InspireEd_UK Website: https://www.inspire.education/