Today you can define mental math in various different ways. Some would say, memorizing times table and remembering the solutions can form the part of mental mathematics. Some would say ability to perform simple calculations in your head can be mental mathematics. Today there are three formal methods available to learn and practice mental mathematics.
One of the method we all know is quite common, traditional way of rote memorizing the times tables. We all remember those days when some of us dreaded going through the most boring and arduous task of rote memorizing. This method works well however the process of achieving the feat, the ability to flawlessly perform hard, difficult multiplications in head is nothing but plain simply boring. On the other hand this method also has limitations when it comes to performing basic calculations; addition, subtraction, multiplication and division, of large numbers. If you are able to multiply 23 x 12 in your head, that is excellent, and you probably can do it because you have the table memorized. But then what if you have to multiply 3487 x 234 with out any calculator?
One can argue that we never perform such large calculations in our day to day life. I agree because as a twenty nine year old I too do not perform these kind calculations in every day life. But do you remember your high school days where we had to perform such large calculations during our math exams? In countries like India many of the times some children are unable to finish the exam papers because they are slow at calculating. And in India, children are not allowed to use tools such as calculators during high school years to prevent children from becoming dependent on such gadgets.
Today, there are two other formal methods available for us as well as children to learn math. Two formal methods that can change a child's perception of boring math to fun and exciting math. Two formal methods that will allow the children to perform difficult, large and long calculations within matter of few seconds, without any external aide of calculator or computer or even the simplest pen and paper, in their head. One method is Abacus Mental Math method and another is Vedic Mental Math. Both of these methods have their roots in Asia.
Abacus Mental Math method has it's root in the eastern Asia, whereas Vedic Mental Mathematics method has it's root in southern Asia. Abacus Mental Math is taught using centuries old tool called Abacus whereas Vedic Mental Math method is taught using the old scripts from India but without any tool.
Goal of Abacus method is to teach and practice simple calculations such addition, subtraction, multiplication and division. But one can perform calculations of very large numbers and long problems mentally. One can also perform squares and square roots but these two are based on multiplication and division respectively.
With Vedic Math one can learn not only about simple calculations and but also complex mathematics such as algebra, geometry and statistics. Some of the most advanced, complex and arduous problems can be solved using Vedic Mental Math method with extreme ease.
If either of these methods are learned since early age, a child aged 14 can perform calculations easily during his or her examinations of Algebra and Geometry. The student can finish exams within the time limit of two hours and be assured to achieve good grades.