COUNTING and NUMBER PATTERNS by 2s, 5s, and 10s
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NUMBER SENSE
Number sense refers to a group of skills that allows students to develop a deep understanding of numbers. In grades One and Two, we develop number sense to 20 by estimating, representing numbers in multiple ways, by exploring equality and inequality while using the symbols > < and =, by subitizing, and by composing and decomposing numbers.
These concepts are described below and are accompanied by videos that will help reinforcing these skills while working with your child at home.
These concepts are described below and are accompanied by videos that will help reinforcing these skills while working with your child at home.
Estimating: when students estimate, they make good guesses using their knowledge of numbers. Estimating helps students perform mental math by helping them judge whether their calculations are accurate.
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Equality and Inequality: students learn to describe numbers as greater than, less than, or equal to as well as use the symbols > < and =.
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Representing Numbers: students are expected to represent numbers in many ways including as: numerals, words, tally marks, with base 10 blocks, on a 10 frame, and as pictures.
Subitize: when students subitize, they learn to quickly identify the objects in a set without counting. Subitizing helps develop number fluency.
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Composing and Decomposing Numbers: composing and decomposing numbers shows the relationship between a whole and its parts. When you combine parts into a whole, you are composing (which is a first step towards adding). When you decompose a number, you break a number into its parts (which is a first step towards subtracting).
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PLACE VALUE
Numbers are made up of digits. The value of the digit depends on its place in the number. Students are continuing to develop an understanding of decomposing numbers (breaking them into their parts) and place value while in order to strengthen their ability to add and subtract numbers beyond 10.
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SUBTRACTION
Subtraction is finding the total, or difference, by taking away. When we build a subtraction question, we take a whole set of objects (such as 20 counting bears) and remove a set to find the difference. We record the answer using numerals to discover how that looks as an equation.
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SUBTRACTION - MENTAL MATH STRATEGIES
Counting Back - Counting back is used when you are subtracting 4 or less; students begin with the minuend (the number from which another number is being subtracted) and count back to find the difference.
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Thinking Addition - when using the mental math strategy, Thinking Addition, students use their knowledge of addition facts to solve subtraction equations as addition and subtraction are inverse operations.
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ADDITION
Addition is finding the total, or sum, by combining together. When we build an addition question, we take two sets of objects (such as 12 counting bears and 8 counting bears) and join the two sets together to find the sum. We record the answer using numerals to discover how that looks as a number sentence. Students practice addition in a variety of ways in order to develop a quick recall of addition facts to 10.
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ADDITION - MENTAL MATH STRATEGIES
Counting On - Counting on is usually used when you are adding four or less; students always begin with the largest addend and count on to find the sum.
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Doubles - You use the mental math strategy of doubles when you add two of the same number. Doubles are all around us including two hands, two feet, ten fingers, ten toes, and four wheels on vehicles. Doubles are learned through repeated practice. The following videos provide variety so that doubles can be practiced over and over.
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Making 10: When using the Making Ten strategy, students practice the number combinations that add up to ten such as 5 +5, 6 + 4, and 7 + 3. This helps students develop quick recall of addition facts. Ten Frames are used to help students build and visualize 10.
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PATTERNS
Patterning is a fundamental concept in mathematics from which much of mathematical understanding is built; this article, "10 Reasons Why It is Important to Understand Mathematical Patterns" provides a good overview of the significance of patterns.
We are learning that a pattern is something that repeats over and over again. We make patterns using sound, movement, and objects. We create and identify a unit, such as ABBA, and extended that unit over and over again. We learn to name patterns using actual objects, such as geometric shapes, and then translate those patterns into numbers and letters.
We are learning that a pattern is something that repeats over and over again. We make patterns using sound, movement, and objects. We create and identify a unit, such as ABBA, and extended that unit over and over again. We learn to name patterns using actual objects, such as geometric shapes, and then translate those patterns into numbers and letters.
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DATA
As we got to know each other during our All About Me theme, we shared our interests and ideas by collecting data and creating, describing, and comparing concrete graphs. Click on this link for an introductory Brain Pop Jr. video about tally marks and graphing. Once on the Brain Pop Jr. site, you can click on "game" and "word wall" for activities that mirror what we are doing in class.
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