Appetizers and Lessons for Mathematics and Reason  ( Français)  
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 Logic mastery is key to easing or avoiding learning difficulties in work & studies. 

Online Volumes (Book Orders)
1,  Elements of Reason. 1996
1A. Pattern Based Reason  1995
1B. Math Curriculum Notes 1996
2. Three Skills for Algebra  1995
3.
Why Slopes & More Math 1995

Site  Folders for Instructors & Adults
A. Public Policy Essays
B.  Mathematics  Education Essays  2006-7
C -Logic & Applied Math Program  
    for education,  June 22, 2008 
D. Quebec English Math Ed -  Standards to
 avoid  in course design & teacher education 
E. Help your child or teen
How TOs/ Ref.-08- 2008
1. Arithmetic Reference
2. Algebra 
3. More Algebra 
4. Geometry  
5. More Geometry
6. Calculus
7. Logics in Maths
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In for a penny, in for a pound

Page Sections: 

Writing began in 1990 to report ideas to local educational authorities for review and refinement in a way that would count.  The bureaucratic impossibility of that, a reflection of the extreme publish or perish competition in academic life, implied silence until retirement (about 2020).  Instead, self-publication followed offline in 1994 and online in 1995. Those ideas included inductive principles (or standards) for instruction and three starter lessons (three skills for algebra, two logic puzzles, why slopes - a calculus preview ), statistically if not universally effective 1983-89). Those three lessons by themselves could have changes the course of mathematics instruction in the 1990's.  Today Site how-TOs go further.  They  supports the inductive principles and standards essentially in full. Today, educational authorities need to re-design secondary mathematics from arithmetic to calculus with the aid of site innovations and its inductive principles and standards, which Occam's Razor yet favour over constructivism.    


Common Needs and High School Mathematics

Secondary and primary school  should aim deliberately  to define, reinforce and enlarge the common knowledge of mathematics.  What does TCPITS  - The Common Person In The Street - need?  

With the high failure rate in calculus, there should be other ends for high school mathematics.That should include mastery of numerical,  geometric and algebraic methods and concepts for solving routine problems and for recognizing when those methods fails.  In particular,  a textbook for learning a second language will not only cover the  spelling  and grammatical rules and patterns (exceptions included), it will may also introduce everyday activities to serve as a stage for introducing or employing words and grammar.  There-in a model for mathematics education.  Numbers are everywhere in street signs, on clocks and in money matters.  Geometry too appears in the use of maps and designs, and   in construction in the home or at work.  And algebra in form of the forward and backward use of the compound interest formula (chapters 14)  and of geometric sums appears in banking, loan, mortgage and annuity matters (chapters 21-5)  Apart from high school mathematics topics required only in calculus (or in engineering and space travel),  preparation for calculus may serve these other ends while serving the other ends can be a platform for re-enforcing skills and concepts required by calculus. The challenge for high school course design is to include  routine or common topics whose potential or importance is clear or can be honestly and not artificially emphasized, so that each course for the most part are relevant to common needs.  That would be besides  i topics and skills explicitly identified as present due to calculus only  or mostly.  In the latter case remarks  and digression mentioning routine calculations in chemistry, physics, biology, accounting, and local construction or work trades would provide further ends and value to skill and topic mastery.  See critical path analysis below.  

Mathematics Teaching Methods and IssuesOnline Volume Mathematics Curriculum Notes  begins with inductive principles for skill and concept development and then points to olde flaws and inconsistencies in the exposition of mathematics which predate and continue in course design today. Inductive principles  provide standards for course design and delivery, simple subject-based, results oriented, and with site how-TOs, provide in draft form at least  a full set of values, ends and means for instruction, direct or indirect, which address or avoid a multitude of  content difficulties - expositional gaps and inconsistencies in modern mathematics curricula and their successors, diluted or not. Some gaps were inherited from earlier times. Mathematics education, if was an empirical art, would collect how-TOs easily understood and repeated in the classroom, and document them for instruction and self-instruction. Site pages explore remedies, logically designed but not fully tested in class - due to  qualification insufficient for employment in education.  Clear and precise skill and concept is a must -  technical gaps in exposition should but filled - but they need to be accompanied by discipline or motivation, so that students will follow instruction..  Why bother to require students to attend school, year after year, when motivation & discipline for schooling  are dilute or absent?  Calculus is a motivation for  high school mathematics. Yet we need to  identify the arithmetic, algebra and geometry  in scenes from daily life and work to say where is the math and how it helps, otherwise there are motivational gaps. 

International Curriculum Reform

Site how-TOs in accordance  inductive principles for education. offer the framework for  an applied  mathematics program. The program  which may  be woven into the existing mixed or applied  mathematics curriculum in the UK and elsewhere. The program instead of repairing and reinforcing the modern mathematics curricula in North America and Scandinavia of the mid-1950s onward, as initially intended,  gives a logically-consistent successor  . The modern mathematics curricula pretense of following or supporting a context-free development of modern mathematics from set theory stumble and  ceased to be context-free  with the mixed or applied mathematics  introduction of coordinates and drawings in the development of  Calculus, trig and analytic geometry and, if taught, Euclidean Geometry. Secondary-level  modern mathematics curricula was inconsistent  in that arithmetic with the decimal representation of numbers was   avoided in theory - not recognized in axioms  but  required and used in practice. Site how-TOs provide a consistent remedy that may be followed from arithmetic to calculus to set the stage for applied disciplines and the optional study of modern, context-free, mathematics at the undergraduate and university level. 

Site how-TOs are logically developed and consistent, modulo the applied math assumption of geometric practices - those present in geometrical use of maps and plans with and without the use of coordinates. Occam's Razor may favour them and inductive principles for their development and refinement. 


Goals and Methods for 
Mathematics Education

Mathematics programs for primary and secondary schools need to  be based on tried and tested methods in accordance with  inductive principles. For instruction with a lean  inductive program to follow,  student performance will be a guide to remedial measures, what steps to retry as is or in expanded form, and what is next in skill and concept development.    Mathematical induction indicate how induction in general will fail if steps are too large or not reachable. Leanness follows from  foresight based on   Occam's Razor or critical path analysis.  In that analysis  subprograms of study and effort, will little or no benefit, those not required by later skill and concept development, may be questioned if not omitted. Finally, there is a question of motivation for programs of study. The key question that needs to be clearly answered is as follows. What are the ends to be met? There may be more than one: (i) an operational mastery of numbers and mathematical methods needed in daily life with clear and plentiful examples to span the needs and maintain mastery without too much duplication; (ii) development of lawyer-like reading abilities for greater skills and awareness in work, study and citizenship;  (iii) calculus and preparation for it.  Site material supports  the last two ends, at least in part.

Sphagetti programming is a term that applies to code that is bloated or needs replacement.  In such code or any code, subprograms that have input but no output may be removed.  CPM is needed to identify that sphagetti

Transparency is required in course design.  Calculations involving lengths, areas, volumes, weights, further measures (direct or calculated) can be placed in a context.  Drill and practice with them may be cast in context or situations fictional or not, but not too specialized.  Course design could present a variety of activities in daily life and identify the mathematics in them as part of skill and concept development or as a motivation for the latter. When may before, during or after.  Mathematics instruction may emphasize the applications as ends in themselves and as tools to develop, refine or consolidate skills and comprehension that will reappear in further applications and/or the further development of the subject alone and with others.  Each topic in mathematics should be accompanied by a clear statements in written and spoken remarks of  the one or more of the following: (i) where it will be needed in daily life (local variety possible), and (ii) where it will be employed in  mathematics or science. Each technique should be named  or have an apt descriptive phrase, for example compound growth formula, rectangle area calculation,  completing the square,  to permit oral and written reference and discussion, and pointers to where it may be used. 

Example: Quadratics are employed in physics to describe projectile motions. Quadratics are also required in the further mastery of  polynomials, geometry and calculus,   

That motivation would be offered besides skill and comprehension development and verification in accordance with inductive principles. Students and teachers become pawns and cogs in a bureaucratic machine when course design does not mention means, values and ends. The latter may be short and long-term.  The latter may also require some compromises.  The most direct route to the long-term ends may be too dry and at the expense of early ends, means and values that could motivate and drive learning and teaching.  Preparation for (a)  calculus and (b) for engineering  in secondary school is a long route.   Motivation should not be contrived nor too artificial.

Example:  Compound growth and decay formulas, and geometric sums too, appear in money matters in the description of compound interest and investment growth/decay, and in loans, mortgages and pension plans calculations.  The same or similar mathematics appears in the description of population growth,  animal husbandry, and radioactive decay.   The forward and backward use of compound interest or compound growth and decay formulas requires a knowledge of logarithms, roots and exponentials.

Explanations as to why topics are covered should be brief, simple and non-fictional, or if fiction or nearly so, presented as food for thought.  While  rates  and proportions, probability and averages are  be useful in daily activities or pleasures,   the study of quadratics, further  polynomials is motivated in all or almost all by calculus. Economic models and calculations involving quadratic functions in particular  provide food for thought, and should be presented as such, rather than as great  application and great motivation for the study of quadratic and further polynomials.  Preparation for calculus provides the simplest explanation, even if that be dry and boring.  Offering motivation is fine, but artificial motivation should be presented as such - food for thought and/or exercises to develop or verify mastery.  

Meeting the demands and requirements of calculus would be a long term goal. In preparation for calculus, instruction may emphasize the value of being able to apply arithmetic, algebraic and geometrical methods  in a show-work, repeatable, reproducible and verifiable or correctable manner.  The ability to apply rules and patterns one at a time, one after another, alone or in combination, with or without comprehension of why those rules and patterns work,  is a sign of care and diligence and a prerequisite to intelligence in such applications. 

The ability to follow rules and patterns in one subject is a sign of specialized intelligence. With regrets, it is  not a guarantee of general intelligence. C'est la vie

The thought-based development of mathematics is based on rules and patterns drawn from experience (or not)  and then assumed. An axiom in mathematics is simply an assumed pattern. 

Exercise for Parents, Students and Teachers - Keep a record of all the out of school mathematics (arithmetic, geometric, algebraic) that you meet  That should give you a list of uses and frequencies.

The student of calculus or before may be advised to learn to do, and worry about the why later.  That push towards rote learning has merit. While a comprehension of the origins and motivations for rules and patterns in mathematics is desirable,  the thought-based development of mathematics is based on the careful and even mechanical application of rules and patterns, alone or in sequence and in combination, to provide results or further rules and patterns to follow. Comprehension in mathematics and its thought-based development is based on the ability to see, follow and apply rules and patterns alone or in combination, one at a time, one after another.  Once that ability appears,  the student who has learnt by rules and patterns by rote,  in a plug and play manner,  may return to their study to replace their rote mastery by a thought-based mastery. 

For instant in developing site pages, I realized I had learnt decimal methods for arithmetic by rote and not understood their origin. Site pages provide a remedy. Site pages endeavor to provide a thought-based development and combination of the rules and patterns required in calculus itself, and in what the latter demands from arithmetic, algebra, geometry and logic.  Those pages, quickly written, are presently in need of polishing.  But for that, they are done.  

The thinking part of an art or discipline:
(repetition of preceeding theme)

The deductive thinking part of an art or discipline comes after the assumption & careful  mastery of some rules and patterns, steps and methods, practices and conventions.  Careful mastery means you can use the rules and patterns etc to arrive at results in a repeatable, reproducible and, if hence verifiably right or wrong manner.  The thinking part of a subject begins when you start to combine rules and patterns, steps and methods, practices and conventions, to obtain new ones in a repeatable, reproducible and hence verifiable manner. 

Thinking or critical thinking within an art or discipline continues through recognizing the benefits, origins and limitations of rules and patterns, steps and methods, practices and conventions, so that the approximations in the application of the latter are known or avoided.  The combination of rule and patterns, customs and practices, steps and methods, one after another, may lead to short parallel strands of reason and hence a thought-based development of an art or discipline besides and even on the empirical mastery of rules and patterns etc with confidence building results that should be  repeatable,  reproducible and hence verifiable. 

Once the ability to form or follow strands of reasons within an art or discipline is present and respected or appreciated, fuller and fuller thought-based developments can be offered, if not in class, then in print. The first phase of education could be based on rote - here are the facts and methods - learn to use them in a repeatable, reproducible and hence verifiable right or wrong manner.  Later phases may then build on that via a mix of deductive and rote mastery of further rules and patterns. That is to say deductive reason need not be explicitly axiomatic. 

 The young mathematic student  for instance may benefit from a thought-based mastery of decimal methods for addition, comparison and subtraction, a comprehension built inductively from examples without or before the formal deductive IF-THEN use of implication rules.  But the young student in learning decimal methods for multiplication and long division would not immediately benefit from an immediate in-class thought-based explanations of why the methods work.  None the less, skill and confidence in their results might and should follow from drill and practice, and methods for verifying or checking results.   Later on, arithmetic methods may be employed as part of deductive arguments with the implicit assumption that they work - give correct results.  That being said, site pages include and point to the thought-based development or mastery of decimal methods for multiplication in full and long division at least in part.

Teachers:  Site how-TOs, inductive principles, and values also give and define a necessary alternative to constructivism and like Alice in Wonderland, subjective theories of education. Ideas that cannot be expressed on paper with diagrams, words and symbols are not part of observable skill & comprehension.  Compare and contrast that view with the Allegory of the Cave in Plato's work The Republic where knowledge is based on shadow interpretation. Compare and contrast that view with the dominant constructivist theory of skill and concept  learning, in which mastery is a subjective affair, not for observation nor correction in an objective manner; and in which changes in delivery style in a shadowy manner was suppose to lead to a subjective (anarchistic) view of knowledge, one that in retrospect resembles the state of knowledge before striving for objectivity was the norm in science and  technology, if not law.  

Ends, Values and Means: 

  • The will and ability to read notes and textbooks like a lawyer, so that no nuance, no subtlety and no clause  escapes  attention is an end, values and means for mathematics education in the training of students and in course design and delivery. 
  • Skill and confidence in  mathematics, a written art or discipline,  may follow from care and precision in following and recording the steps in methods and routines in a well-formatted, readable, reproducible and repeatable manner for verification or correction. Here care and precision is another end, value and means for skill and concept development. 
  • Mastery of  thought-based paths for understanding and developing skills, concepts and comprehension is a further end, value and means for mathematics education, and may be considered an extension of the care and precision, required so that no subtlety, no clause and no detail escape attention..

Rote Learning Coexists with the thinking part of mathematics.

Writing began to support and strengthen the thought-based development of mathematics along the lines of the modern mathematics curricula of the mid-1950s onward.  Identification of gaps in exposition and logic in Volume 1B, Mathematics Curriculum Notes,  did not change that plan. It indicated more work to do.  As a late 1960's student of the modern mathematics curricula, I was engaged or hooked by its purported thought- and logic-based development, Euclidean style of mathematical knowledge. Thus  I was against rote learning. 

In retrospect rote learning co-exists with thought-based development of skills and concepts in mathematics. 

(1) At the high level, in  the introduction of calculus, students are given key theorems (rules and patterns) to apply and told the proofs are too complicated for immediate mastery - site pages may lessen the level of complication, but the advice to mastery the key theorems and learn how to apply, but to skip the proofs still applies. As a student, I did not like the gap that represented in my skill and concept development.

(2)  Precalculus students will learn formulas for areas and volumes via mix of rote learning and derivation. The formulas that cannot be derived before calculus can be derived or explained as applications of calculus in the form of slope calculation reversal (integration).

(3) Site pages point to the inductive (drawn from experience) and thought-based development of primary and secondary school mathematics. But in decimal arithmetic, the easy inductive or thought-based mastery of place-value addition, comparison and subtraction aids skill development. But multiplication and long division methods, must for late primary and early secondary school, are easily mastered by rote but may be too complicated for a thought-based development. The latter may come, if it comes at all, at the senior high school level. 

Note: Calculus requires and extends the earlier full strength use of algebra in secondary mathematics. The latter in turn requires a full strength mastery of exact and approximate arithmetic with the decimal format of numbers alone or in fractions.  That mastery begins in primary school. 

The coverage of arithmetic, algebra, geometry and even calculus in site pages was intended to eliminate rote learning in mathematics education, and provide a thought-based development instead in accordance with inductive principles and standards for instruction in rule and pattern based arts and disciplines - those advocating or striving for  objectivity.  Yet as indicated some rote learning is needed in the development of arithmetic.Mathematics education, yours or mine, may have involved more rote learning than need-be.  Some pages were written to provide myself a thought-based understanding of skills and concept met earlier by rote. 

Mathematics education may become a bureaucratic set of rituals in rules and patterns are mastered one a time and one after another  because that is required for a forthcoming end of year final examination, without any further foresight into the aims, ends and even values that might be part of mathematics education. Preparation for calculus provide one end, albeit the high failure rate in calculus makes one wonder if the route to calculus is too hard for students - does it represent a pyramid scheme in which many start and few benefit.  The remedy for that is to include along side and even as part of preparation for calculus, an identification and  development of the arithmetic, algebraic, geometry and even logic routines and methods that are present and useful in daily life. That should be besides the development of skills and topics explicitly required by calculus.  Then each course would provide useful and hence motivated skills and concepts.  

Is it possible for students to end their studies in mathematics before calculus is manner that provides skills and confidence along side the decision not to prepare further for calculus?  

Students need to master routine methods for  the routine mathematical questions that appear in daily life. The question what would not work  in society if there were no numbers, no compound interest or no growth formulas, no geometric sums, no geometry  (maps and plans include) might motivated consumer or people-oriented mathematics studies along side calculus preparation. I suspect most students and teachers, and guidance counselors, are unaware  that preparation for calculus is or was the reason - the only possible reason -  for many or most topics in secondary and primary school mathematics.  Preparation for calculus should set a standard for and not a hidden agenda in earlier skill and concept development. 

Each course mathematics represents an opportunity to see and recognize the though-based development of skills and concepts.  Students may enter with a mastery of rules and patterns (we hope), some mastered by rote and some with a thought-based development.   In the course,  further rules and patterns may built on earlier ones or built separately by emphasizing the origins and derivations from immediate observations or previously met if not mastered rules and methods, regardless of how those earlier rules and methods were met and (?) mastered. The latter emphasis represent the introduction or continuation of the though-based development of skills and comprehension.  Courses are generally too short for a full review of earlier rules and patterns with a thought-based development.  Modulo that, or except for that,  each course may stand on a mix of rote and thought-based learning to provide a thought-based development via the careful use of rules and patterns alone and in combination to get results or to imply further rules and patterns.  

Students may object to the thought-based development of skills.  That development may not be tested and hence not required by forthcoming final examinations.  Students may be in learn only what is required for the final. They may be no long-term goals. Further more, students may not appreciate explanations of rules whose earlier rote mastery gives results, repeatable and reproducible, or not - It works, why do we need to see more, may represent the underling attitude or question, to which there is no reply.  And students may object to the inclusion of a development of a rule or method, and ask instead rote mastery of the rule and method with minimum explanation and many examples.  Most activities outside of mathematics are plug and play. There is no need to ask why.  That sets a standard, not optimal, for mathematics education. It represents the view, give us the formula and numbers to plug in it.  Such student needs to be in courses which emphasis routine problem solving skills for the multiple ways in which mathematics touches daily life.  Students aiming for calculus would be benefit from a solid grounding the precalculus application of mathematics, every one is likely to meet. 

The thought-based development of mathematics is not for all. There are some dilemmas and gaps in the exposition of high school mathematics that will not be fully addressed here.  Course design and promotion needs to reflect a critical path analysis of what is to be done and why.  Site pages identify what might be included in secondary mathematics as preparation for calculus and as aid (?) to routine problem solving likely to be needed in the lives of students and families - problem solving with geometry and money matters say.  The challenge is to provide a mathematics education with aims, methods and values that students and teachers can appreciate.

The Rote, Plug and Play, Descriptive,  Aspect of Education in Science and Technology

Question: How can the latter be reduced? Can it?

Mathematics is an art and discipline in which a thought-based development is possible on first meeting or on review, revision or consolidation of its skills and concepts.  Most can be developed with drawing and writing instrument (pencil and paper or modern successors included). In contrast, science, and technology in theory and in practice has become plug and play.   The cook in the kitchen often and the chemist rely on bought ingredients, properly labeled. The high school and college science or technology  lab may include instruments that are used in a plug and play manner. The use of electronic balances may provide greater accuracy and convenience, but they also represent that plug and play aspect of a school or college lab.  The use of balances where physical weights are employed is closer to the origins of science and technology, more primitive, but less plug and play.  That is to suggest simple measurement of mass and volume may be done in the school lab.  The use of batteries, ammeters and voltmeters represent a further plug and play element of the school or college science lab. Is it possible to verify Kirchoff's current and voltage laws with them? I tried and failed.  The foregoing raises the question of how to illustrate chemistry, physics and biology in lab in a way that will confirm or corroborate theories alongside their in class description in a manner that is, minimally plug and play. Dissection in biology does not count as artificial  plug and play. In the classroom, the periodic table represent a cumulative effort which can be described as is with its development, and its modern variations. But it cannot be derived.   And in chemistry, students may be surprised by parallel theories which disagree on the identification of acids, bases and salt.   The term acid-salt refers to a compound that when dissolved in water is  acidic (turns litmus red) while the chemical formula theory suggested it should be a salt.  Students may have to view science and technology as a plug and play process in which methods are subject to verification - do they give repeatable and reproducible results in practice, and in which theories, hypothesizes or hopes  are subject to refutation (it does not work) or partial success, small or wide ranging,  instead of absolute confirmation. 

North American Instruction - Contrutivism

Do you insist on putting a round peg into a square hole  Does it make sense for subjective complicated, incompletely defined  theories of knowledge to be applied to mathematics or science - these being arts and disciplines striving for objectivity? The answer is no.  The attempt to do so lends an Alice in Wonderland experience for students and teachers in precalculus mathematics in North America and less so in the UK. The majority is not always right.    

  The 1990 NCTM standards and principles  fail to  answers to two concrete questions:  What mathematics is to be taught, why and how.  The 1989 standards as is and reformulates in year 2000 focuses on delivery, constructivist style and so represent a subjective view of knowledge in which teacher or discipline centered view instruction (my discipline has many steps,  let me cover them)  is replaced by calls  individuals to construct their own comprehension from authentic, realistic, genuine  activities.    Yet most primary and secondary school instructor do not have a calculus background - the motivation for much of secondary school mathematic program, its content, and many are seconded from other disciplines, impressed into mathematics instruction. Pre-1990 expositional difficulties in mathematics in the form of steps too large or missing and in form of expositional inconsistencies are also  not recognized.

The NCTM standards ignore the  instructor content mastery problem  and expositional difficulties, while  calling for and a specifying  a subjective delivery style, and depreciating rule and pattern mastery as a form of rote learning.   Contrast that with the old fashioned view good figuring skills were necessary to demonstrate intelligence. Contrast that with the Euclidean model for rule and pattern based reason prized in the work of Euclid and in modern mathematics.  Contrast that as well  with the content of Volume 1A, Pattern Based Reason, and its description of the origin, benefits and limitations of rule and pattern-based processes in thought and deed in mathematics and science.  Modern society, for better or worse, with great variation,  strives for objectivity and not subjectivity in the development and application of rules and principles  in law, mathematics, science and technology.  Site how-TOs and inductive principles and standards (or lower bounds)  for instruction support the latter.  The NCTM needs a change of course. 

 

Mathematics Education  Essays etc

Area Intro
Ideas for Better Instruction
4 Ways to Improve Reform
Theory of Knowledge
Peer Review
The Trouble With Algebra
Course Design and Delivery
How Letters Appear
Sit Down & Study
Modern Education
Key Notes and Themes
Site Lesson Plans
How This Site Differs
Site Origins
Math & Logic Puzzles
Comments on site content.

Words For Instructors
Inductive Principles
Fairness Principles
Apprentices & Masters
In for a Penny
Constructivism and Cognitive Theory
Three Remarks
For a Leaner Curriculum
Mixed Maths Curricula
Cultivating Intelligence
Reason - 3 kinds in maths
Logic in Mathematics
Science Education
Maths Instruction in General
Operational View & Values
Standards
Ends and Values
Goals & Unifying Themes
Algebra Lesson Plans
Algebra, Geometrically
Mathematics Curriculum Shifts
Teaching Tips - Fractions to Calculus
Math Ed Perils
Talk the algebra talk
Sec I  - Fraction Focus
Sec II -  algebra focus
Sec III - Focus on Slopes
Maps-Plans-Drawings
Math Wall Posters
Education, Empirical Art
Damage Reversal
North American Math Curriculum
Managing Reform
Essay January 2007
Educational Follies
Contructivism Incomplete
Missing the Point I
Mathematics in Context
What and When, A Challenge
Grouping Students
Teacher Certification
Education of Math Ed. Professors
Site Eurekas
Links


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