2021/4/11

Addition is a binominal operation.
Appreciations

Free Program for SEAMEO School Networkfrom the University of Tsukuba, Affiliate Member of SEAMEO

Teaching Mathematics to Develop Mathematical Thinking as Higher Order Thinking:

How do you teach? Why?

Review

Additional sentence to explain manipulation of concrete and semi-concrete object at the beginning.

Lesson 6: Introduction of Subtraction
Reflection

Isoda, Masami. Prof., Faculty of Human Sciences
Director of CRICED, The University of Tsukuba, Japan
With collaborations ofRevitalizing
Teacher Education

Curriculum Standards: SEABES-CCRLS( by SEAMEO-RECSAM (Mangao, Ahmad, Isoda; 2017)

Left↓
Difference

VSExplanation by sentences
4By using what children learned!
Review
Task sequence for preparation of future
Difference-Situation

Number• Existence andnecessity• Order

Difference↓Left

If children write thesituation by 2+2=4 insteadof 4-2=2 at the
introduction of subtraction,
how do you assess?

Subtraction ofDifferent Sets

Larger orSmaller
Greater or Less
• Operations

Math expression
Addition: operation
Math sentence
addition

Counting VS Adding

How many times did children experience?

Task Sequence of Addition (1)Do you remember how 0 was introduced in L2?
Getting proficiency of meaning and skill

In Japan:
Make sense (understandmeaning)
Think about how to
calculate/operate/find theeasier way to answer
Acquisition of proficiency
Try to teach how to extend
the number

If children answer thesituation 7+5 =12 bycounting, what preparation
is missing in yourteaching?

What children already prepared?
 On content
 On Thinking and Process On Values and Attitudes

Review

Permanence of Form

How do you teach subtraction?
Left-Situation
Why?

Story Problems
Mathematical Modeling
Altogether Situation A, B, C, …
Concrete Object
Explanation with blocks
manipulative
Semi Concrete Object

Acquisition

Nguyen Chi Thanh, TEH Kim Hong and Wahid Yunianto
Adopting a 21stCentury Curriculum

HOTS isMath. T.

Task sequence what students already knew.

ReviewUsing what you already knew!

Task sequence for preparation of future learning:

Review

Addition activity for what?

Questioning to others (Attitude), Easier & Beautifulness (Value)
Composite and de-composite of numbers(content), Cardinal Number (content, idea), Compare (idea)

What is addition?

Review

On situations in our life: It is the object for addition.
• Altogether, Increase, Different Sets: the ways of translations
and conceptualization• It can be answered by counting.
• If counted, it is not the answer of addition but the sameanswer with counting on natural number.
• Counting is necessary for the confirmation of sum on naturalnumber.
On the world of number (mathematics): not denominatednumber/not quantity• Number(Existence/ necessity, set/cardinal), Order, Operation• Addition is a binominal operation;
It cannot be answered by counting but answered by memorizedcalculation such as composite of numbers.

• Operation put the structure into Number Set!
Children find anotherbeautiful structure/pattern of numbers
by using equivalenceclass on addition

Equivalence class:4~(2+2), 4~(1+3). 4~(3+1)(2+2)~(1+3)? (1+3)~(3+1)?
Commutativity, Associativity• Addition is the inverse operation of subtraction.

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2021/4/11

Could you explain task sequence for subtraction (1)by using learned terminology on Lesson 1~6?

Could you explain task sequence for subtraction (1)by using learned terminology on Lesson 1~6?

References16Could you explain task sequence for subtraction (1)by using learned terminology on Lesson 1~6?

References
Masami Isoda, Raimundo Olfos edited (2020). Teaching Multiplication with Lesson Study: Japaneseand Ibero-American Theories for International Mathematics Education. Cham, Switzerland: Springer.

(Open Access)
Masami Isoda, Aki Murata (2020). Study with your friends: Mathematics for Elementary School (12vols.). Tokyo, Japan: Gakko Tosho.
Masami Isoda, Aki Murata, Aida Yap (2015). Study with your friends: Mathematics for Elementary
School (12 vols.). Tokyo, Japan: Gakko Tosho.
Masami Isoda, David Tall (2019). Mathematics for Junior High School (3 vols.). Tokyo, Japan: GakkoTosho.
Dominador Dizon Mangao, Nur Jahan Ahmad, Masami Isoda edited (2017).SEAMEO basic education

standards (SEA-BES): Common core regional learning standards (CCRLS) in mathematics andscience. Penang, Malaysia: SEAMEO-RECSAM, http://www.recsam.edu.my/sub_seabes/images/docs/SEAMEO-ASEAN-Curriculum-SEABES-CCRLS-Standards.pdf

Maitree Inprasitha, Masami Isoda, Patsy Wang Iverson, Ban Har Yap (2015). Lesson Study:
Challenges in Mathematics Education. New Jersey, USA: World ScientificMasami Isoda, Shigeo Katagiri (2012). Mathematical Thinking: How to develop it in the classroom.
New Jersey, USA: World Scientific

TEH Kim Hong, ISODA Masami, GAN Teck Hock (in printing). Mathematics Challenges for Classroom
Practices at the Lower Primary Level. Penang, Malaysia: SEAMEO-RECSAMISODA Masami, TEH Kim Hong, GAN Teck Hock (in printing). Mathematics Challenges for Classroom
Practices at the Upper Primary Level. Penang, Malaysia: SEAMEO-RECSAMGAN Teck Hock, ISODA Masami, TEH Kim Hong (20augi21). Mathematics Challenges for Classroom
Practices at the Lower Secondary Level. Penang, Malaysia: SEAMEO-RECSAM

Gakko Tosho: Study with your friends:
Mathematics for Elementary School Series

Could you explain task sequence for subtraction (1)by using learned terminology on Lesson 1~6?

Primary School Textbook
2001 Curriculum2005 Japanese Edition
2005 English Edition↓
2010
Thai Ed.

2005 Edition

10 Editions

2010 Edition

Junior High S. Textbook
2012 Curriculum2016 Japanese-Edition
2019 English-Edition2020 Indonesian-Edition
202X Thai Ed.

4 Editions

Isoda, M., Tall, D. (2019). Junior High School
Mathematics Textbook, Gakko Tosho

4 Editions

NEWEST EDITION

2012 Mexico Ed.
2019 Chile Pro. Ed.
2011 Curriculum2011 Japanese Edition
2011 English Edition↓
2019 Papua N.G. Edit.
2020 Indonesian Edi.
2020 Chile Ed.
2015 Japanese-Edition
2015 English-Edition2020 Curriculum2020 Japanese Edition2020 English Edition152