Genghis Khan’s grandson, Khubilai Khan, introduced a paper currency intended for use everywhere and attempted to create primary schools for universal basic education of all children in order to make everyone literate. The Mongols refined and combined calendars to create a ten-thousand year calendar more accurate than any previous one, and they sponsored the most extensive maps ever assembled. The Mongols encouraged merchants to set out by land to reach their empire, and they sent out explorers across land and sea as far as Africa to expand their commercial and diplomatic reach.