If I let my child learn accelerated math / rapid mental math such as jones geniuses or using abacus, no doubt it will help to stimulate right brain and solve maths problems in a very fast way.
1. In the school system, students have to show the workings and calculation in solving the maths problem (i'm not sure how the schools system in other countries work, but for my school the marks are allocated to my workings shown in the exam paper). This is especially for primary/secondary schools. E.g. if question is 234526+737383, the student can straight away give answer using rapid mental math and write the answer without showing the calculation in vertical format, there will be zero mark (the teacher might think that the student cheated in class).
2. My maths teacher in high school told me before, we must work out step by step calculation/working (e.g. In algebra) towards our answers because maths is a logical subject (it's called deduction?). And if we are able to do maths in such way it will train us to think logically.
My question is: if I teach my children using rapid mental maths, will this cause him/her to lose the ability to show step by step workings in math problems? Or ability to think logically?
Any opinion or advise on this?