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Kindergarten to Grade 2 / Session #4. Welcome to …. … the exciting world of. Counting and Developing Early Multiplication Concepts. Everything we do in Kindergarten to Grade 2 is the foundation of later mathematical understanding. Big Ideas in NS&N that pertain to PR.
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Welcome to… …the exciting world of Counting and Developing Early Multiplication Concepts
Everything we do in Kindergarten to Grade 2 is the foundation of later mathematical understanding.
Big Ideas in NS&N that pertain to PR • Numbers tell how many or how much. • Classifying numbers or numerical relationships provides information about the characteristics of the numbers or the relationship. • There are many equivalent representations for a number or numerical relationship. Each representation may emphasize something different about that number or relationship. • Our number system of ones, tens, and hundreds helps us know whether we have some, many and very many. • The operations of addition, subtraction, multiplication and division hold the same fundamental meaning no matter the domain to which they are applied.
Counting • Counting involves both reciting a series of numbers and representing a quantity by a symbol • First experiences with counting are not initially attached to an understanding of the quantity or value of the numerals • Counting is a powerful early tool and is intricately connected to the other four ‘Big Ideas’
Principles of Counting Stable Order Principle 1,2,3,4,5,6… not 1,2,3,4,6,8,9,10
6 6 3 3 5 5 2 2 1 1 4 4 Principles of Counting Order Irrelevance Principle OR 6 in this group 6 in this group
Principles of Counting Conservation Principle
Principles of Counting Abstraction Principle
Principles of Counting The Abstraction Principle Can Also Look Like…
Principles of Counting One-to-One Correspondence
Principles of Counting Cardinality Principle 1 3 5 7 2 4 6 8 8 hearts
1 2 3 4 5 Principles of Counting Movement is Magnitude Principle
Principles of Counting Unitizing Hundreds Tens Ones
From Five to Ten! • Children build on their concept of 5 to develop a concept of 10. • They consolidate their concept of quantities of 10 in relation to the teens and decades. • They can use this foundation to understand that the digit 1 in 10 represents a bundle of ten.
Quantity • Quantity represents the “howmanyness” of a number and is a crucial concept in developing number sense. • Having a conceptual understanding of the quantity of five and then of ten are important prerequisites to understanding place value, the operations and fractions. • An early understanding of quantity helps with concepts around estimating and reasoning with number, particularly proportional reasoning.
Relationship Between Counting and Quantity • Children don’t intuitively make the connection between counting and their beginning understanding of quantity. • With rich experiences using manipulatives, they gradually learn that the last number in a sequence identifies the quantity in the set that is being counted (cardinality) • This is an important beginning step in linking counting and quantity.
Quantity and Mathematical Reasoning • Children need continued experience with all types of manipulatives to understand that each quantity also holds within it many smaller quantities. • Developing a robust sense of quantity helps children with mathematical reasoning.
We Need to Revisit Often! • Quantity is not a simple concept that children either have or do not have. • Children need experience in repeating similar types of estimation (and checking) activities to build up their conceptual understanding of the amount of something. • Resist the temptation to move too quickly into just using numbers!
Constructing Understanding of Multiplication A continuum of conceptual understanding
Beginning in Early Primary • Skip counting • Must be connected the actual count of objects • Must be connected to many different models • Students see the Movement-is-Magnitude principle of counting • MUST BE BOTH FORWARD AND BACKWARD
Beginning in Early Primary • Skip counting should be seen as a method for counting more quickly and strongly connected to the counting of real objects or people
Beginning in Early Primary and continuing throughout Primary • Skip counting models • Rote skip counting focusing on the aural aspects of the rhythm of the chant • Counting real things • Counting money • Number line • Hundred chart / carpet • Rekenrek • Five frames and ten frames • Base Ten materials (late Primary)
Beginning in Early Primary • Skip counting • Teachers begin to show the representation of adding the same quantity over and over again. • Teachers connect the model and the symbolic representation of repeated addition to the number of times the quantity is added. • This should be shown as “I added 2 6 times to get 12.” AND “I added 6 groups of 2 together to get 12 all together.” 2 + 2 + 2 + 2 + 2 + 2 =12
Beginning in Early Primary • Skip counting • This should be shown as “I added 2 6 times to get 12.” AND “I added 6 groups of 2 together to get 12 all together.” Let's say it together! 0 1 2 3 4 5 6 7 8 9 10 11 12 2 + 2 + 2 + 2 + 2 + 2 =12
Beginning in Early Primary • Skip counting • This should be shown as “I added 2 6 times to get 12.” AND “I added 6 groups of 2 together to get 12 all together.” Let's say it together! 2 + 2 + 2 + 2 + 2 + 2 =12
Mid - Primary • Skip counting • All work is initially modeled by the teacher, who shows these connections many times, INFORMALLY at first, then explicitly. • Once the students have seen many examples of repeated addition, and the symbolic representation with the addition symbol, the connection can be made to standard notation: 6 groups of 2 6 x 2
Late Primary • Skip counting 3 groups of 5 make 15. (5, 20, 15) 3 x 5 = 15
Late Primary • Geometric models • Using the array model (lining up objects into rows and columns) • Begin to work with square tiles to make arrays with different quantities
Late Primary • Geometric models • Using the array model (lining up objects into rows and columns) 3 groups of 5 make 15 3 x 5 = 15 5 groups of 3 make 15 5 x 3 = 15
Late Primary • Geometric models • Begin to work with square tiles to make arrays with different quantities • How many different rectangles can you make for 12 tiles? What equations are represented by each arrangement? 3 x 4 = 12 and 4 x 3 +12 2 x 6 = 12 and 6 x 2 = 12 1 x 12 = 12 and 12 x 1 = 12
Late Primary • Geometric models • Focus on the commutative property • a x b = b x a • Does turning the rectangle ¼ turn yield a different rectangle? • Is 3 x 4 always the same as 4 x 3? 3 x 4 = 12 and 4 x 3 +12 1 x 12 = 12 and 12 x 1 = 12 2 x 6 = 12 and 6 x 2 = 12
Late Primary • Geometric models • Focus on the relationship of the row and column lengths as the array is rearranged: as the number of columns doubles, the number of rows is halved. 4 2 1 3 6 12
Late Primary • Geometric models • Focus on the relationship of equality among the different representations. 4 2 1 3 6 12 4 x 3 = 2 x 6 = 1 x 12