Everything, without exception, is changing in this century! Institutions as old as us, humans, such as family and marriage are getting fundamentally redefined world over, including India! Is math also changing, especially the way we must be taught and the way we must learn it.
Yes, 21st century math is fundamentally different because the logical part of math is finally the useful math, arithmetic is now commoditised in calculators, mobile phones! Even the complex arithmetic/calculations are most easy achieved using mobile phones.
Actually, ‘math = arithmetic/calculations + logic’, and this has been true for all times we know about math, but the lack of ‘calculators’ brought the focus of math on arithmetic/calculations (e.g., one couldn’t buy or sell things unless one knew the mathematical calculations).
With the ubiquitous mobiles, calculation abilities are minimally relevant, and valuable (despite X and XII board requirements for calculations) for life and career. Anyway, when we think of putting focus of math education and learning on logic, it’s not at the cost of arithmetical abilities; in fact, conceptually sound knowledge of logic significantly ensures arithmetical advantages.
Thus, 21st century math education is about extensive focus on logic, reasoning, exploration, daily life applications, and secondary focus on applying the logical thinking to arithmetically apply math in real life.
In other words, 21st century math education is about ‘no rules/methods’ math, everything must be experienced, played with, touched and felt in daily life; in fact, the every rule, method, and formulae must be ‘discovered’ by the children themselves, based on the experiences, or debates, in the math classrooms.