Visit any Kindergarten class and ask the children what they want to be when they grow up. Chances are great that many of them will choose one of the above professions. Chances are equally as great that none of them will say they want to be a Mathemagician.
A Mathemagician? If you had asked this question of a young Arthur Benjamin, a mathemagician is probably what he would have answered. Several years later and true to his word, Arthur Benjamin has become a well-known and highly respected Mathemagician. Dr. Benjamin is also a Professor of Mathematics at Harvey Mudd College in California, and an author and frequent talk show guest. But the “magical” part about Dr. Benjamin is that he possesses the unique and amazing talent of being able to mentally calculate three digit squares in less time than it takes using a calculator. He can also tell you the day of the week on which you were born when given just the date. He has even memorized the decimals in Pi to 100 digits using a mnemonic device based on a phonetic code. In short, his mathematical skills are so fantastic that it is difficult to imagine that they are anything less than magic. But what do these amazing feats have in common? They are all accomplished through the use of mental math.
So by now you are (hopefully) intrigued and possibly wondering how this anecdote relates to Posnack students. This year, Posnack students are focusing on strengthening their mental math skills. More than just rote memorization, mental math requires students to develop a greater understanding of math concepts so that they may think critically and approach problem solving in a logical manner. Mental math also provides a foundation by which students can more easily progress to higher-level mathematics and strengthen their ability to gauge the reasonableness of their solutions.
As the school year progresses, you will be seeing how our students are developing their mental math skills by demonstrating a strong understanding of number sense. From the Kindergarten and First Grade students using their Soroban Abacus, to the Third Grade students multiplying multi-digit numbers from left to right, to the Upper School students using bar models to break down the intricacies of word problems – these are all ways in which the Posnack teachers are building upon the relationship between critical thinking and mental math.
Are you still wondering if there is really such a thing as a Mathemagician? Watch Dr. Benjamin’s TED talk at http://www.ted.com/talks/arthur_benjamin_does_mathemagic.html . He will turn you into a believer before you can say Abracadabra!