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From Wikipedia

Math wars

Math wars is the debate over modern mathematics education, textbooks and curricula in the United States that was triggered by the publication in 1989 of the Curriculum and Evaluation Standards for School Mathematics by the National Council of Teachers of Mathematics (NCTM) and subsequent development and widespread adoption of a new generation of mathematics curricula inspired by these standards.

While the discussion about math skills has persisted for many decades, the term "math wars" was coined by commentators such as John A. Van de Walle and David Klein. The debate is over traditional mathematics and reform mathematics philosophy and curricula, which differ significantly in approach and content.

Advocates of reform

The largest supporter of reform in the US has been the National Council of Teachers of Mathematics.

One aspect of the debate is over how explicitly children must be taught skills based on formulas or algorithms (fixed, step-by-step procedures for solving math problems) versus a more inquiry-based approach in which students are exposed to real-world problems that help them develop fluency in number sense, reasoning, and problem-solving skills. In this latter approach, conceptual understanding is a primary goal and algorithmic fluency is expected to follow secondarily.

A considerable body of research by mathematics educators has generally supported reform mathematics and has shown that children who focus on developing a deep conceptual understanding (rather than spending most of their time drilling algorithms) develop both fluency in calculations and conceptual understanding. Advocates explain failures not because the method is at fault, but because these educational methods require a great deal of expertise and have not always been implemented well in actual classrooms.

A backlash which advocates call "poorly understood reform efforts" and critics call "a complete abandonment of instruction in basic mathematics" resulted in "math wars" between reform and traditional methods of mathematics education.

Critics of reform

Those who disagree with the inquiry-based philosophy maintain that students must first develop computational skills before they can understand concepts of mathematics. These skills should be memorized and practiced, using time-tested traditional methods until they become automatic. Time is better spent practicing skills rather than in investigations inventing alternatives, or justifying more than one correct answer or method. In this view, estimating answers is insufficient and, in fact, is considered to be dependent on strong foundational skills. Learning abstract concepts of mathematics is perceived to depend on a solid base of knowledge of the tools of the subject.

Supporters of traditional mathematics teaching oppose excessive dependence on innovations such as calculators or new technology, such as the Logo language. Student innovation is acceptable, even welcome, as long as it is mathematically valid. Calculator use can be appropriate after number sense has developed and basic skills have been mastered. Constructivist methods which are unfamiliar to many adults, and books which lack explanations of methods or solved examples make it difficult to help with homework. Compared to worksheets which can be completed in minutes, constructivist activities can be more time consuming. (Reform educators respond that more time is lost in reteaching poorly understood algorithms.) Emphasis on reading and writing also increases the language load for immigrant students and parents who may be unfamiliar with English.

Critics of reform point out that traditional methods are still universally and exclusively used in industry and academia. Reform educators respond that such methods are still the ultimate goal of reform mathematics, and that students need to learn flexible thinking in order to face problems they may not know a method for. Critics maintain that it is unreasonable to expect students to "discover" the standard methods through investigation, and that flexible thinking can only be developed after mastering foundational skills.

Some curricula incorporate research by Constance Kamii and others that concluded that direct teaching of traditional algorithms is counterproductive to conceptual understanding of math. Critics have protested some of the consequences of this research. Traditional memorization methods are replaced with constructivist activities. Students who demonstrate proficiency in a standard method are asked to invent another method of arriving at the answer. Some teachers supplement such textbooks in order to teach standard methods more quickly. Some curricula do not teach long division. Critics believe the NCTM revised its standards to explicitly call for continuing instruction of standard methods, largely because of the negative response to some of these curricula (see below).

Reform curricula

Examples of reform curricula introduced in response to the 1989 NCTM standards and the reasons for initial criticism:

Critics of reform textbooks say that they present concepts in a haphazard way. Critics of the reform textbooks and curricula support traditional textbooks such as Singapore Math, which emphasizes direct instruction of basic mathematical concepts, and Saxon math, which emphasizes perpetual drill.

Reform educators have responded by pointing out that research tends to show that students achieve greater conceptual understanding from standards-based curricula than traditional curricula and that these gains do not come at the expense of basic skills. In fact students tend to achieve the same procedural skill level in both types of curricula as measured by traditional standardized tests. More research is needed, but the current state of research seems to show that reform textbooks work as well as or better than traditional textbooks in helping students achieve computational competence w

Murderous Maths

Murderous Maths is a series of British educational books by author Kjartan Poskitt. Most of the books in the series are illustrated by illustrator and author Philip Reeve, with the exception of "The 5ecret L1fe of Code5", which is illustrated by Ian Baker, and "The Murderous Maths of Everything", which was illustrated by Rob Davis. The Murderous Maths books have been published in over 25 countries. The books, which are aimed at children aged 8 and above, teach maths, spanning from basic arithmetic to relatively complex concepts such as the quadratic formula. The books are written in an informal similar style to the Horrible Histories, Horrible Science and Horrible Geography series, involving evil geniuses, gangsters, love stories and smelly burgers. The author also maintains a website for the series, which has has been running for the past 10 years[http://www.murderousmaths.co.uk/].


The first two books of the series were originally part of the "The Knowledge" (now "Totally") series([http://www.kjartan.co.uk/books/books.htm]), itself a spinoff of Horrible Histories. However these books were eventually redesigned and they, as well as the rest of the titles in the series, now use the Murderous Maths banner. According to Poskitt, "these books have even found their way into schools and proved to be a boost to GCSE studies". The books are also available in foreign editions including: German, Spanish, Polish, Greek, Dutch, Norwegian, Turkish, Croatian, Italian, Lithuanian, Korean, Danish, Portugese, Hungarian, Finnish, Thai and Portuguese (Latin America) [http://www.murderousmaths.co.uk/books/books.htm]. In 2009, the books were redesigned again, changing the cover art style and the titles of most of the books in the series.

Poskitt's goal, according to the Murderous Maths website, is to write books that are "something funny to read", have "good amusing illustrations", include "tricks", and "explaining the maths involved as clearly as possible". He adds that although he doens't "work to any government imposed curriculum or any key stage achievement levels", he has "been delighted to receive many messages of support and thanks from parents and teachers in the UK, the USA and elsewhere".


The following are the books that are currently available in the series.

  • Guaranteed to Bend Your Brain (previously Murderous Maths), ISBN 0-439-01156-6' - (+ - x / %, powers, tessellation, roman numerals, the development of the "10" and the place system, shortcomings of calculators, prime numbers, time - how the year and day got divided, digital/analogue clocks, angles, introduction to real Mathematicians, magic squares, mental arithmetic, card trick with algebra explanation, rounding and symmetry.)
  • Guaranteed to Mash your Mind (previously More Murderous Maths), ISBN 0-439-01153-1' (the domino and pentomino, length area and volume, dimensions, measuring areas and volumes, basic rectangle/triangle formulas, speed, coversion of units, mobius strip, pythagoras, right angled triangles, irrational numbers, pi, area and perimeter, bisecting angles, triangular numbers, topology networks, magic squares.)
  • Awesome Arithmetricks (previously The Essential Arithmetricks: How to + - × ÷), ISBN 0-439-01157-4' - (odd even and negative numbers, signs of maths, place value and rounding off, manipulating equations, + - x / %, long division, tames tables, estimation.)
  • The Mean & Vulgar Bits (previously The Mean & Vulgar Bits: Fractions and Averages, ISBN 0-439-01270-8 (fractions, converting improper and mixed fractions, adding subtracting multiplying and dividing fractions, primes and prime factors, reducing fractions,highest common factor and lowest common denominators, Egyptian fractions, comparing fractions, converting fractions to decimals, decimal place system, percentages: increase and decrease, averages: mean mode and median.)
  • Desperate Measures (previously Desperate Measures: Length, Area and Volume, ISBN 0-439-01370-4' (measuring lines: units and accuracy, old measuring systems, the development of metric, the SI system and powers of ten, shapes, measuring areas and area formulas, weight, angles, measuring volume, Archimedes Principle, density, time and how the modern calendar developed.)
  • Do You Feel Lucky? (previously Do You Feel Lucky: The Secrets ofProbability, ISBN 0-439-99607-4' (chance, tree diagrams, mutually exclusive and independent chances, Pascal's Triangle, permutations and combinations, sampling.)
  • SavageShapes(previously Vicious Circles and Other Savage Shapes, ISBN 0-439-99747-X' (signs in geometric diagrams, Loci, constructions: perpendicular bisectors; dropping perpendiculars; bisecting angles, triangles: similar; congruent; equal areas, polygons: regular; irregular; angle sizes and construction, tessellations and Penrose Tiles, origami, circles: chord; tangent; angle theorems, regular solids, Euler's formula, ellipses, Geometric proof of Pythagoras' Theorem.)
  • The Key To The Universe (previouslyNumbers: The Key To The Universe, ISBN 0-439-98116-6' (Fibonacci Series, Golden Ratio, properties of Square, Triangle, Cube, Centred Hexagon and Tetrahedral numbers, "difference of two squares", number superstitions, prime numbers, Mersenne primes, tests to see if a number will divide by anything from 2-13 and 19, finger multiplication, binary and base 8, perfect numbers, irrational transcendental and imaginary numbers, infinity.)
  • 'The Phantom X (previously The Phantom X:Algebra, ISBN 0-439-97729-0' (variables, elementary algebra, brackets, factorising, expanding, and simplifying expressions, solving quadratics and the quadratic formula, "Think of a number" tricks, difference of two squares, coefficients of (a-b)n, linear graphs: co-ordinates; gradients; y intercept, non-linear function graphs including parabolas, simultaneous equations: substitution and elimination, dividing by zero!.)
  • The Fiendish Angletron (previously The Fiendish Angletron:Trigonometry), ISBN 0-439-96859-3' (scales and ratios in maps and diagrams, protractor and compass, SIN, COS and TAN ratios in right angled triangl

From Yahoo Answers

Question:Estimate the answer please 428x68= 12.74x4.89= 5493 divided by 63= 128.4 divided by 2.8= Please help what is the answer by estimating

Answers:430 x 70 = 30 100 12.7 x 4.9 = 62.23 5400 / 60 = 90 129 / 3 = 43

Question:Please explain how to estimate by using front end estimation 546-234 Do I need to round off to the nearest....? Please help and thanks

Answers:I would loosely say 550 - 250 = 300; .... or 540 - 240 = 300 whereas actual answer = 312 ... so semi-close and in the ballpark. if you could get closer, you would probably be able to do the actual problem in your head.


Answers:Estimate - give a ballpark guess, don't do the actual math 68.4 8.72; lets round to the nearest whole number 68 9; how many times does 9 go into 68 without going over? 9*7 = 63 the 63 leaves us 5 short. This bums the 7 up to 7.5 7.5 <------Estimated Answer Actual Answer 7.84 Blessings

Question:I live in seattle and adding new 225 square footage to my rambler home. The plan is to extend an esixting bed room a bit and add a bath. Bath room size is 12'6" * 7'7". Double sink, shower and toilet. Basic fittings... I got the permit. Cultured marble for sinktop and shower walls. I am getting around 28,000 as estimate from multiple contractors (parts & labor . Taxes included). Is this reasonable price? Please advice. Thanks in advance.

Answers:The average price is between $100/sq. ft to $200/sq.ft depending in the type of construction & the amenities. $28,000 is about ballpark

From Youtube

How to make a ballpark estimate for subtraction :Watch as Aubrey shows you how to make a ballpark estimate for subtraction

Math Activity - Estimations :An activity that uses estimates to build math skills.