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Patterns & A Relations/Function s based approach to Algebra

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Patterns &

A Relations/Functions based approach to

Algebra

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Does this look as familiar to you…….as it does to me?

P r i m a r y S c h o o l F i r s t Ye a r T h i r d Ye a r

3 x 6 = 18

7 + 5 = 12

7 – 5 = 2

X + 5 = 12X + 5 – 5 = 12 – 5X = 7

3x = 183x = 18 3 3X = 6

2x = 6X = 3

3x = 18X = 18 - 3X = 15

X + 5 = 12X = 12 + 5

2x = 6X = 6 -2X = -3

Procedure overtaking

Understanding

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“National and international mathematics assessments during the 1980s and 1990s reported that secondary

school students, in order to cover their lack of understanding, resorted to memorizing rules and

procedures and that students eventually came to believe that this activity represented the essence of algebra (e.g., Brown, Carpenter, Kouba, Lindquist, Silver, &

Swafford, 1988).”Carolyn Kieran

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JC OL - 2006

“Common mistakes were : combining terms leading to oversimplification and transposition errors."

JC HL - 2006

“Areas of weaknesses in candidates answers: Handling transpositions in algebraic type equations.”

LC FL - 2005

“There were.......transposition errors”. “Transposing accurately and with understanding is certainly a difficulty. ”

LC OL - 2005

“Average candidates experience difficulty with all but the most basic ofalgebraic manipulations and can cope only with basic routines in solving equations .”

Chief Examiners’ Reports

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How can we develop in our

students, a deeper understanding of what Algebra is?

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The Historical Development

ofAlgebra

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Before 250 A.D. • Ordinary language

descriptions used for solving problems

• No symbols or special signs to represent unknowns

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c. 250 A.D.• Diophantus introduced the use of

letters for unknown quantities.• There were no procedures on how

to use algebra.• Diophantus’ maths was still

presented as a story of how to do things.

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3rd to 16th Century• Algebra was used to get a result for

the unknown: For example = 9• They were not using algebra to

express the general case.

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Late 16th Century• Vieta read the work of Diophantus

and began to use a letter for a given, as well as an unknown

• Now it became possible to express general solutions.

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Also in late 16th Century• It was now possible to use algebra

as a tool for proving rules governing numerical relations.

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Latest Development• Procedures for governing

algebra.

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QuestionIf the procedures were the latest development…

are we doing the right thing, introducing students to the procedures so early?

Should we introduce Algebra in the same natural way it was discovered?

???

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Concept of Equality

In Primary School:The equal sign is seen as an instruction.3 plus 5 equals what?

3 + 5 =a + b =

In Post-Primary School:

Students need to see the equal sign as now meaning equality.

37 + 41 = 38 + 40 x + y = (x + 1) + (y – 1)

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Old Syllabus New Syllabus

ExpressionsProceduresEquations

??? ???ExpressionsProceduresEquations

Project Maths Syllabus

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“Mathematics……the study of patterns”

Pattern

Conjecture

ProofFormula

Procedure

Patterns

Pattern

Observe Generalise

“algebra as a systematic way of expressing generality” Syllabus

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Concrete

Abstract

Words Abbreviations

Numbers Variables

Arithmetic properties of Numbers

Arithmetic Properties of Algebra

“algebra as generalised arithmetic”

Syllabus

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We will discover algebra through the Multi-Representational approach: • Story• Tables• Graphs• Manipulative Models• Equations

“representational activities”

Syllabus

Multi-Representations

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Relationships & FunctionsThrough looking at relationships a student can be naturally and organically introduced to:

• Symbols• Variables• Expressions• Simple equations • Inputs and outputs of a function• Visual representation of algebra before ever learning

procedures

“emphasise relationship based algebra”Syllabus

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A Functions based approach to Algebra

“…..enable learners to have a deep understanding of algebra which allows easy movement between equations, graphs, and tables”

“The common introductory course provides the initial engagement with patterns, relationships and expressions, laying the groundwork for progression to symbolic representation, equations and formulae.” Syllabus

Patterns T&L

Extend to the potential of the T&L

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Key outcomes and words: Identify patterns and describe different situations using tables and graphs,

words and formulae Generalise in words and symbols A variable Independent and dependent variables Constant rate of change as that which characterises a linear function Inputs and Outputs ‘Start amount’ - Table

- Formula- y-intercept of a graph

Rate of change of the dependent variable - Table - Graph as a ‘slope’

- Formula y = mx +c Constant rate of change Identify linear relationships as having constant first differences between

successive y values (outputs) Know that parallel lines have the same slope (same rate of change of y with

respect to x) Connect increasing functions with positive slope, decreasing functions with

negative slope and constant functions with zero slope

Project Maths publication “A Functions based approach to Algebra”

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