Place Value Rocks!

I think it is important to teach children what the base-ten number system is and why we use it. Having this knowledge helps children understand where numbers come from and why it makes sense to use place values.  So, do you know where the base-10 number system originated? The Egyptians first came up with a base-10 number system around 3100 BC.  However it is believed that the Incas also used it. Then around 300 – 200 B.C. the Hindus began attaching a symbol to each number.  They also created a name for each power of 10. Today we use ones, tens, hundreds and so on. The Hindu-Arabic numeral system originally had 9 digits but around 600 AD, the Hindus invented a symbol to represent nothing. We call it zero. In 700 AD, the Arabs discovered the Hindus’ numeral system and in 800 AD, a mathematician from Persia wrote a book about it.  It was translated into Latin about 300 years later. Eventually the Hindu-Arabic numeral system was introduced to Europe and the rest my friends is history! I like to introduce place value by telling a little pretend story about a caveman who likes to collect rocks. This is how it goes:

There once was a caveman who liked to collect rocks. His pile of rocks kept getting bigger and bigger until there was no more room in his cave. One day the caveman's friend came over. He said, "Ohh-gah! Ohh-gah! (the students love this part) How many rocks do you have?" The caveman had no idea. So, he decided to put a tally mark on his cave wall to represent each rock in his collection. Soon his cave wall was filled with tally marks. The caveman's friend came over again. "Ohh-gah! Ohh-gah! How many rocks do you have?" The caveman looked at the cave wall and scratched his head.   He decided to put the rocks into groups of 10. He represented each group of 10 with a stick.  Soon he collected so many sticks that he decided to put the sticks in groups of 10 as well. So, for every 10 groups of 10 sticks, he exchanged it with a flat stone (which represents 100). The next time his friend came over he said, "Ohh-gah! Ohh-gah! How many rocks do you have?" The caveman replied, "I have 5 stones (flats), 8 sticks (rods) and 7 rocks (units)." 

Hopefully you get the idea. My students love this story and it helps them understand why we need place value! Since place value is part of the common core, I created four place value games. You can purchase them at my TPT store here if interested.