Mayan Numbers

One of the emphases in math here in Guatemala is Mayan numbers. In Pam's opinion, it's a lot of wasted time considering they don't really use them for any practical purpose. Here at La Senda, they mainly learn them for the national math competition the kids participate in. Miss Anita showed me the system: the frame looks like dominoes, upended and stacked on top of each other the larger the number is. Dots, horizontal lines, and eyes symbolize the numbers; rather than having a base of 10, the base is 20 (I think--it goes ones, twenties, four hundreds, etc). I think maybe I've heard about it before. I tried out a few numbers and got them right; however, adding and multiplying them sound like quite a chore to learn.