Mental Mathematics – Abacus

We took our daughter to Brain Child Institute for an assessment of whether she is ready for a math class at this time. Her kindergarten starts next fall which is 14 months away, so we were curious to introduce some math and reading to her at this time.

(image source: http://managemyemissions.com/images/abacus.jpg)

At the center, we visited a class room of 5 kids, they were probably 1st graders I think, and noticed a teacher keeping saying bunch of numbers for addition & subtraction viz., 3 + 5 + 2 – 3 + 1 + 6 + 2 – 8 + 7 , whats the answer? to my surprise, one of the kids, who was probably not distracted with our entry there, did answer it right. wow! How did he do it.

I noticed a strategy they used with their fingers, not necessarily abacus, but the I was told, they had started with abacus initially and now through imagination. I have never used abacus in my life, although i have seen one during my childhood, but my assumption was it was used to teach count the numbers for kindergarteners. well, that’s the limit of abacus usage I knew about until today when I noticed it at school and recently someone had mentioned about it. 

Have you used Abacus in school or to learn mathematics? to what extent?

To add on to this in my experience, Mental Mathematics, once learned the strategy, it is pretty cool.

Thinking about this and tutoring and classes for mental mathematics for basic operations like addition, subtraction, multiplication and division, although we see a lot of hype and promotions with organizations/institutions like Kumon, Brain Child, etc, however, L’ and I were thinking about it, and looking at the corner store retailer in Bangalore, the roadside vegetable and fruit stall vendor, where they would not have even gone to the primary schooling, and they perform these math perfect. here is the picture:

“A vendor with bunch of fruits and vegetables with a measuring weight at the front. There are 5 different people around the stall picking up things and having them weighed at random. PersonA gets egg plant, tomatoes, beans, – all are different quantity;  person B gets 5 different vegetables; and they all get ifferent items with different quantities. When each individual asks the shopkeeper for the amount they owe now, he gives the right answer for each individual, and mentally (no paper or computer or Retail Point of Sale machine involved – note he is selling on a roadside) he knows who picked what and how much. He computes the amount accordingly and gives the number.

amazing …