Tuesday, August 7, 2018

Sowell - Skewed Distributions

The causes of skewed distributions of outcomes are many.
"In recent times, virtually any disparity of outcomes is almost automatically blamed on discrimination, despite the incredible range of other reasons." 



Note: Thomas Sowell ​taught economics at Cornell, UCLA, Amherst and other academic institutions. Currently, Sowell is a scholar in residence as a Senior Fellow at the Hoover Institution, Stanford University. I first noticed him when I read Dismantling America in 2010. Also, he wrote Wealth, Poverty and Politics 2016. His most recent book is Discrimination and Disparities 2018. Gerald P. O'Driscoll, Jr., Senior Fellow, Cato Institute, writes, “In this provocative book, Thomas Sowell turns the table on those who automatically link disparate outcomes to discrimination. He begins by focusing instead on the myriad of factors that need to come together for success." Read the book.   ​

Thomas Sowell (Discrimination and Disparities) says that many policy fixes in education have been counterproductive, such as immediately blaming gaps in educational outcomes on discrimination. Too often, skewed distributions of educational outcomes were wrongly blamed on "genes or discrimination," observed Sowell. The playing field has never been equal and cannot be made level by government "equity crusades," which are "fallacies of fairness." In short, the one-size-fits-all equity fix of the Common Core and other efforts will not erase the skewed distributions. Sowell writes, "The idea that it would be a level playing field if it were not for either genes or discrimination, is a precondition​ in defiance of both logic and facts." ​

What irks me as a teacher is that divergence in education is now called discrimination, and that achievement is now called privilege. It is typical liberal rhetoric that is offensive to all hard-working students who achieve, including students of color. Sowell points out, regrettably, that "in recent times, virtually any disparity of outcomes is almost automatically blamed on discrimination, despite the incredible range of other reasons." (Sowell calls it the invincible fallacy. I call it  a sham when scholarship and achievement are criticized with empty rhetoric.)

The social vision and rhetoric of progressives "treat beliefs as sacred dogmas beyond the reach of evidence or logic." Facts don't matter much! "Facts seem to have become irrelevant, for all too many people, who rely instead on visions and rhetoric."​ 

Also, the idea that inputs do not influence outputs is another issue. ​Of course, they do! Sowell explains, "To admit that inputs affect outputs, whether in education in the economy or other areas, would be to undermine the [social] vision and agenda" [of progressive ideology]. According to Sowell, the invincible fallacy is that "outcomes in human endeavors would be equal, or at least comparable or random, if there were no biased interventions, on the one hand, nor genetic deficiencies, on the other." The invincible fallacy assumes "an even or random distribution of outcomes in the absence of such complicating causes as genes or discrimination."​ The assumption, of course, is wrong! 

The causes of skewed distributions are many. Indeed, life, itself, is unfair, yet "fallacies of fairness" abound in our classrooms. All students get the same instruction under Common Core and state standards regardless of their math achievement, which should drive outcomes to be the same. Not Really! It is wishful thinking. Outcomes would not be the same. The crux is that even if the inputs were the same, which I doubt would be possible, the outputs would still not be the same! As Sowell says, "Equal inputs does not produce equal outputs."

Incidentally, one of the many consequences of the invincible fallacy has been the "dumbing down of education."

Comments: ThinkAlgebra@cox.net

©2018 LT/ThinkAlgebra

Friday, August 3, 2018

STEM

What does STEM mean?
Science - Technology - Engineering - Math

This post is a work in progress. Expect frequent changes. 
The quotes highlighted yellow with a 🔻 triangle symbol are from Nick Arnold, STEM QUEST.

Model Credit: McKaylaS

Click: Visit my New Science Page!

Only 22% of 12th-grade students are proficient in science (NAEP). The Next Generation science standards limit core content in science, especially in chemistry and physics, which are lumped together. Also, many believe that the only way to learn science is through hands-on, inquiry stuff. That's not true! Most science is learned by reading and studying textbooks, in coursework, and from lectures by knowledgeable teachers. Students do not need to reinvent the wheel, not in science or math. Lab experiments are done to reinforce the content taught.  

Below, MIT Professor Catherine Drennan lectures chemistry to over 300 freshmen students packed into a huge lecture hall. Students had textbook reading assignments to study, problem sets to complete, help sessions to attend, labs to do, and exams to pass. MIT Course: Principles of Chemical Science (5-111sc).


In contrast to the Next Gen Framework, "It is never too early to introduce small children to big ideas,observes Chris Ferrie, a physicist, and mathematician, who wrote Quantum Physics for Babies and similar picture books (Baby University).

In teaching complex material in math or science to little kids, I think Jerome Bruner, not Piaget. LT



We should teach the mathematics needed to do and understand the science such as was done in Science--A Process Approach (1967). For example, four of the six processes taught in SAPA's 1st grade were math or math-related. The science teacher taught math, which was often a year or two ahead of the regular curriculum. Today, there seems to be math anxiety in STEM. University of Chicago researchers Sian L. Beilock and Erin A. Maloney contend, "Our students cannot enter into STEM majors if they have a fear of mathematics." In science, teachers should teach STEM Math Skills. K-6 teachers don't have a coherent science curriculum such as SAPA, which stressed the math link in science. Furthermore, elementary school teachers have weak math and science skills. 


🔻"Iscience, you investigate the world around you." 
Science starts with atoms, atomic structure, and how the universe works, including living things, the Earth, our solar system, the galaxies, and stars. "A is for Atom, B is for Black Hole, C is for Charge," writes Chris Ferrie (ABCs of Physics) for young children. 

"The rules that describe nature seem to be mathematical. Why nature is mathematical is again a mystery. Science is a method of finding things out. The method is based on the principle that observation is the judge of whether something is so or not." Also, according to Richard P. Feynman, basically, scientists guess an idea or rule, then test it through experiment and interpret the observations. "If the rule does not agree with experiment, then the rule is wrong." We don't start with a bunch of observations, then infer a rule. "It does not work that way." In science, we guess a rule, then experiment and examine observations (mostly measurements). The experiment and its results must be repeatable by others. The mathematics must be right. An idea you can't test is speculation, not science. "The purpose of theory is to describe nature, not to explain nature." (Source: Richard P. Feynman, The Meaning of It All)

Note: Technology and Engineering are not science; they are products of science. Mathematics is a tool used by scientists to describe nature.

Contrary to the NextGen science standards, elementary school students should study atoms, which are the building blocks of matter, and important molecules like DNA, along with atomic theory or structure (electrons, protons, and neutrons), quantum physics, chemical reactions, motion (Newton's Laws), electromagnetism, the roles of famous scientists, and other topics. 

In classical mechanics (classical physics), at certain distances, opposite charges are attracted and like charges are repelled. It is simple to show this to 1st and 2nd-grade students with N-S magnets. But, when students learn about atoms, classical ideas don't work.

The negatively charged electron should smash into the very tiny, positively charged nucleus according to classical mechanics, but it doesn't. The electron (-) and nucleus (+) stay apart. Why? Also, positively charged protons in the nucleus of atoms stay put. They don't fly apart. Why? 

The classical mechanics of Coulomb's Force Law and Newton's 2nd Law do not work at tiny, atomic distances. A new way of thinking was needed: quantum mechanics (i.e., Quantum Physics). In fact, Chris Ferrie wrote a picture book called Quantum Physics for Babies


Atoms and molecules exist, move, and bounce off each other. 
(Einstein, 1905)


Chris Ferrie writes, "All electrons have energy. An electron can take energy to jump up an energy level and give up energy to fall down an energy level. A quantum is the smallest unit of energy." There is much more to this, of course, but it is a start.  

🔻"In technology, you develop products and gadgets to improve our world." 
The cell phone is a good example of technology.


🔻"In engineering, you solve problems to create extraordinary structures and machines." Engineering often starts with simple machines. In short, you need to learn some physics. Yet, the simple machines are absent from NextGen science standards. Students can be introduced to engineering by building a bridge or a robot. They can build circuits and design and build a structure with Lego. 

Students can use gumdrops and toothpicks to design and build a stable structure such as a bridge. Shapes are important. 

The Six Simple Machines
Lever
Wheel and axle
Pulley
Inclined plane
Wedge
Screw

🔻"In math, you explore numbers, measurements, and shapes." 
Beginning in 1st grade, it is essential that students get used to symbols that represent numbers and unknowns. Math starts with numbers and equations and how they work. For example, x + x + x = 10 - 4 is a 1st-grade level equation. The symbol x must be 2, which is the only solution to the equation: 2 + 2 + 2 is 6. Students must follow the algebraic rule for substituting. The right side (10 - 4) is 6; therefore, the left side must equal 6. Thus, 6 = 6. 

Math is a major tool of science. An equation can be represented by symbols, pictures (i.e., graphs) or data tables.

Students should study math, especially equations and equation solving. But, to move forward to algebra, they need to master the basics of arithmetic such as whole numbers, integers, fractions, percentages, and ratios.


Learning how numbers work, calculating with numbers, and solving equations are important mathematics in early elementary school. 

In the first lesson for the 4th-grade classes (8-8-18), I introduced a system of three equations, which requires logical reasoning, knowledge of algebraic substitution, and some basic arithmetic. I meet with kids once a week for an hour in my Teach Kids Algebra program.  

z + x = 13
y + y = 14
z + y = 12
x =
y =
z =

==============
A quadratic equation defines an up-side-down parabola at the water fountain.



©2018 LT/ThinkAlgebra


Saturday, July 7, 2018

Math Teaching 2

Running in Place & Fallacy of Fairness
The abstract goes to Concrete
The How always preceded The Why


No matter how hard Alice ran, she stayed in the same place, so has U.S. math achievement. "Faster! Faster! Now here you see, it takes all the running you can do, to keep in the same place. If you want to get somewhere else, you must run at least twice as fast as that!?" (The Queen to Alice, Through the Looking-Glass
Running in Place
Math Achievement Stagnation
For many years, students seem to be running in place in math achievement. It's stagnation. In short, our kids are not getting better at math. They are staying in the same place. Kids are not learning much because the fundamentals are not taught for mastery. Indeed, most teachers do not want to admit that they teach math poorly. Teachers get good evaluations when they teach math the Common Core reform math way. It's group work and test prep. Teachers focus on test-based proficiency not the mastery of content. Even if a student scores at the proficient level on the state test, it should not imply that the student has mastered grade-level content.

The constructivist approach of reform math hasn't worked. Scores on national and international tests have been low. Students are not required to practice arithmetic basics for mastery. 

The only way to judge whether or not the instruction is working is through performance testing. Can the student do standard arithmetic efficiently?  Zig Engelmann writes, "How successful is your version of the constructivist approach?"  

Petrilli: Lost Decade of Educational Progress: 2007-2017
After all the reforms and billions and billions ($) spent over the years, our 4th-grade and 8th-grade students are no better in mathematics than they were 10 years ago. Not only are the math scores below expectations; they are also flat

Michael J. Petrilli says the NAEP scores in math from 2007 to 2017 indicate a "lost decade of educational progress." Also, Bill Gates spent "hundreds of millions to improve teaching," but the initiative "failed to improve student achievement." 

What is wrong with education? More money, various reforms, so-called innovative programs, and professional development haven't worked. We have been unable to improve the "teaching" in the classroom, that is, the teaching that substantially boosts real student achievement

In schools of education, teachers are taught inferior (minimal guidance) instructional methods, unreliable theory, flawed equity and diversity guidelines, and a reform math curriculum that is not world-class. Moreover, K-8 teachers are weak in math and science content because they majored in education, which is not an academic subject. How can they teach subjects they don't know well? I am convinced that some elementary school teachers, today, do not know how to teach math or reading effectively. 

The progressive scheme dumbs down math for equity. High achievers and low achievers are mixed in the same classroom or in the same math class (inclusion for fairness). Furthermore, all students get the same instruction (e.g., Common Core or its state rebrand) regardless of achievement level or ability (equalizing for fairness). Indeed, "equalizing downward by lowering those at the top," says Thomas Sowell, is "a crazy idea," It is a "fallacy of fairness" that hurts all children, especially children of color. In American schools, it has been taboo to sort kids by achievement for math. In contrast, Singapore sorts kids in math in the 1st. grade. All kids should be given opportunities in schooling but not always the same opportunities or the same instruction. Kids who are advanced in arithmetic, for example, need an entirely different math curriculum from other kids. Instead of advanced math, they are given grade-level material. It is called equity, but it is false equity. 

Also, the priority should be given to learning the compact, standard algorithms first, but this is not the case in the reform math as taught in our schools. Starting in 1st grade, we don't stress the mastery of fundamentals. Memorization and drill-to-develop-skill have fallen out of favor in modern classrooms. Group work, discovery learning, and other fads are much more important than automating the fundamentals of arithmetic, progressives (aka liberals) say. They are wrong!


Help
We fell down the Rabbit Hole decades ago! 
Let's say we needed to calculate 6 x 1584. In Mock Turtle's 3rd-grade "Uglification" class, students were taught a wide range of alternative methods or strategies to multiply: lattice, repeated addition, array, area, partial products, make a drawing, calculator, distributive. (Which method should I use?) But, learning all these alternative methods clutters the curriculum and the minds of children (cognitive load). Who multiplies using the area model? The standard algorithm has been pushed aside. Some kids never learn it. Progressive education strikes again. We spend a lot of money, time, and effort on progressive ideas and theories that don't work well. Why make arithmetic harder than it is? 

The Real World: To move forward, students must know the compact, standard algorithms, not complicated alternatives.


Part I Abstraction
Why isn't math taught this way?
We think concrete goes to the abstract because that's what everyone says. But, what if the "experts" were wrong? The idea is that children develop number concepts only from concrete representations, then, later, as abstract ideas (Piaget's theory), but it doesn't work that way. Indeed, 5 is 5 and can be represented in hundreds of different ways such as 5 people, 5 pencils, 5 cubes, 5 dots, etc., but the number 5, itself, is an abstract idea. It is a concept in our mind. You don't need to go from concrete to abstract to understand the meaning of 5. The number 5 is already abstract, which is the starting point. 

The number line helps novices visualize what 5 is. It helps beginners with the idea of magnitude. The number 5 is a point on the number line that is one more than 4 and two less than 7, and so on. 

The meaning of 5 is derived from its connections with other numbers. 

What about 3 + 4? You don't need to show 3 + 4 is 7 in several concrete ways, or make a drawing, or write an explanation. If need be, the number line can verify that 3 + 4 is 7, which is obvious. But the number line is not a proof or a why. Also, showing different ways to represent 3 + 4 is not a verification of "deep understanding" or why 3 and 4 add to 7.

The number line is essential arithmetic, but it is seldom used in the primary grades, which is a huge mistake as children try to grasp magnitude and how numbers behave. 


The Number Line Is Important Arithmetic

Numbers are invented in our minds. They are abstract. Children start with the whole numbers as concepts and should learn connections between numbers on a number line, such as "add 1" (4 + 1 = 5), or 3 + 4 = 7, or 7 - 3 = 4, or 3 x 4 as the sum of three fours: 4 + 4 + 4 = 12. 

So, why do we ask novices to explain the obvious several different ways? We are told that it shows understanding. Really? I don't buy it. If needed, the number line verifies it. That said, 3 + 4 = 7 should be memorized early in the 1st grade, but, unfortunately, the memorization of number facts has fallen out of favor in progressive classrooms

In short, arithmetic is invented in our minds. In every word problem, no matter how simple or complicated, the student needs to pull out the numbers and figure out what to do with them (execute an operation) to find an answer. You see, arithmetic is about numbers that are abstract ideas. It's not about 5 pencils. It's about the 5 and how it relates to other numbers. We use straightforward arithmetic to solve word problems. 

If arithmetic is abstract, then why isn't it taught that way?

Indeed, the equation 3 + 4 = 7 is the solution to hundreds of word problems. In 2nd grade, I would write an equation on the board and ask students to make up a story (word) problem. Some students surprised me by turning 3 + 4 = 7 into a missing addend problem (a subtraction problem) such as, "I have 7 apples and give 3 of them to Bill. How many apples do I have left? Or, 7 - 3 = 4. The problem isn't about apples; it is about the numbers and how they are related. The basic relationship between addition and subtraction is abstract.

Part II
The HOW always preceded the WHY.
Why isn't math taught this way?
Tobias Dantzig (Number: The Language of Science), a book highly praised by Albert Einstein, writes, "In the history of mathematics, the "how" always preceded the "why," the technique of the subject preceded its philosophy. This is particularly true of arithmetic. The strength of arithmetic lies in its absolute generality such as a + b = b + a. Its rules admit of no exceptions: they apply to all numbers. Every number has a successor [add one]. There is an infinity of numbers." Teaching novices arithmetic should be the "how," not the "why." Kids are novices, not little mathematicians. 

Ian Stewart (Letters to a Young Mathematician) clarifies, "One of the most significant differences between school math and university math is proof. At school we learn how to solve equations or find areas of a triangle; at university, we learn why those methods work and prove that they do." We need to stop teaching kids as if they are little mathematicians, which they are not. 

American teachers are hung up on the "why" of everything, but in arithmetic, it is proper to learn the "how" first and the "why" later, which is what happens in Asian nations. Learn the technique first and get it right (i,e., automate it). Learn the "how" first and don't worry about why it works.

Note: Standard arithmetic is simple and compact, but it is not easy to learn without the memorization of single-digit number facts and practice-practice-practice. 

National Mathematics Advisory Panel (2008):
"Computational proficiency with whole number operations is dependent on sufficient and appropriate practice to develop automatic recall of addition and related subtraction facts and of multiplication and related division facts. It also requires fluency with the standard algorithms for addition, subtraction, multiplication, and division." I do not recall teaching arithmetic without some level of student understanding. Understanding develops slowly over the years. Also, automating the mechanics of arithmetic for fast access frees working memory space for problem-solving. Arithmetic is a tool for solving problems.  

First-Grade Subtraction: 
Go Vertical! Let's Borrow! Missing Addend Equations!
The standard algorithm of subtraction is a key math skill that can be taught in the 1st grade. The vertical format is a place value system. Start with problems that don't involve borrowing, such as 47 - 25, but use the vertical format to stress place value.

Teach borrowing
Borrowing shifts a ten back into the ones place, that is, one ten equals 10 onesThe 16 can mean 16 onesIt is simple place value and reverse engineeringStudents can compose missing addend equations in their heads and recall memorized addition facts to solve them. What number plus 9 is 16? {7 + 9 = 16} Or, x + 9 = 16 . It is a missing addend equation. Children can use memorized addition facts to do subtraction: 

addend1 + addend2 = sumIt is important to relate subtraction to addition.

Like it or not, Arithmetic is based on Rules
I often hear teachers say that they don't want kids memorizing a bunch of rules. But, arithmetic and algebra are governed by rules, and students must know the rules and be able to apply them to do correct mathematics. For example, the commutative rule should be learned in the first full week of 1st grade: 2 + 3 and 3 + 2 give the same answerArithmetic is based on rules.  There are not that many, but they should be learned as early as possible, such as the "zero rule" for addition: 3 + 0 = 3. The properties of numbers that children learn are rules. They are also mini procedures.

Learn the procedure first (i.e., the "how," such the procedure for solving 1/2 of 1/2, which is a multiplication of fractions 1/2 x 1/2 = 1/4.)

The stress on understanding "why" something works is misplaced. For example, Isaac Newton invented a calculating method (calculus). He knew it worked because the results of his calculus agreed with the experimental results, but he didn't know why his calculating method worked. The "why" wouldn't come for another 200 years with "limits." But, that didn't dissuade Newton from using his calculating method to figure out physics. It always worked. He worked out the how, but not the why. Still, he was a brilliant mathematician and physicist. 

So, when we teach kids (novices) an operation, such as addition in 1st grade, we should first make sure they can do the procedure well (the "how"), which requires practice-practice-practice. Focus on the how not the why. 

Teachers should teach the procedures (aka algorithms) that are the most efficient and compact and work all the time. These are the standard algorithms

Understanding comes out of doing. Why are parents concerned about their children's math education? Kids can't do simple arithmetic. 

Students Learn Math Inductively
Mathematics uses deductive reasoning and logic to create new math. But, students--who are novices, not experts--don't learn math that way. They learn math inductively. That is, the teacher explains several examples and then tells students that the method always works. It is impossible to test every possible case or present a formal proof. The teacher should also explain the counterexample.

Students don't need to draw pictures or count objects to understand math.
enVision Problem Solving
Kara found 5 shells. Then she found 3 more. How many shells did Kara find? Draw a picture. Write the number. 


The problem-solving idea of enVision Math, a popular reform math program, is for the student to draw little pictures then count the objects depicted. The memorizing of critical single-digit number facts is not part of the curriculum in 1st-grade state standards. In my opinion, 5 + 3 = 8 should be memorized in 1st grade. It can be verified on a number line if need be. Moreover, the answer to the question is "Kara found 8 shells," not the number 8.

Teachers teach math for test-based proficiency, not mastery, and that is what is wrong with math instruction today. Proficiency in state math tests should not imply that the student has mastered grade-level math content. Under Common Core, state standards, test-based accountability, and "teach to the test items" mentality, our curriculum has become fragmented, and our instructional methods have been inferior.

Let me repeat. Educators focus on low achievers. It is called "equalizing downward by lowering those at the top," which is a "fallacy of fairness," says, Thomas Sowell. Instead, teachers should focus on equalizing upward to challenge high achievers by tracking them in at least one of their best subjects, such as mathematics, but not all their subjects. It is tracking-by-subject, but there should always be some flexibility in grouping along with way. 

To Be Revised
Updated: 7-7-18, 7-10-18, 7-11-18, 7-13-18, 7-16-18, 7-17-18, 8-31-18
Model Credit: Gabby, Hannah, Shayna
The NAEP chart is from an article by Michael J. Petrilli (Fordham)


©2018 LT/ThinkAlgebra.org