Base 20? Really? And it's fun?! Read on...
In the primary math department at Seabury School, a solid foundation is laid down through lots of hands-on instruction and investigation. The students can then build upon this foundation and are able to transfer their mathematical knowledge into new situations.
Recently the students experienced this when they applied their knowledge and conceptual understanding of base 10 place value to various bases. Using place value mats and manipulatives, the students first played a game called Race to 100.
Students roll 2 dice and place the number of "units" rolled into the one's place. When there are10 units, a trade is made for a "long" in the ten's place. Trading continues until there are 10 "longs" to trade for a "flat"--a 10 X 10 manipulative that has 100 units.
The students then played a similar game called Race to a Flat. With a solid, conceptual understanding of place value, students can understand the concept of "trading" when the maximum place value is reached.
|In base 6, trades are made when there are groups of 6.|
|In base 5, trades are made when there are groups of 5.|
|In base 4, trades are made when there are groups of 4.|
|We even can understand base 2, the binary system used |
for most modern computer and computer-based devices.
Each digit is referred to as a bit.
We then went on to take the concept further
and tried out some base 20 Maya Math!
Our Maya Math Adventure:
Using sticks for 5, stones for 1 and shells for 0,
we learned the ancient Maya method for writing very large numbers.
We played some practice rounds at an interactive website:
And we got it!!
First and second graders can understand and use base 20.
Lesson learned by this teacher:
never under-estimate the potential of a child!