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Mathematics // Addition & Subtraction
Subtracting multiples of 10Subtract multiples of 10 (10–90) from multiples of 10 using place value strategies
Ages 6 to 7MethodMathematics // Addition & Subtraction
Adding Three Small NumbersAdd three one-digit numbers using strategies including looking for pairs that make 10
Ages 6 to 7MethodMathematics // Addition & Subtraction
Grouping numbers to addUnderstand and apply the associative property of addition: when adding three numbers, any two can be added first
Ages 6 to 7ConceptMathematics // Addition & Subtraction
Addition and subtraction strategiesUse counting on and counting back as strategies for addition and subtraction
Ages 6 to 7MethodMathematics // Addition & Subtraction
Fluent adding and subtracting within 100Fluently add and subtract within 100 using strategies based on place value, properties of operations, and the relationship between addition and subtraction
Ages 7 to 8MethodMathematics // Addition & Subtraction
Fluent adding and subtracting within 20Fluently add and subtract within 20 using mental strategies; know from memory all sums of two one-digit numbers
Ages 7 to 8MethodMathematics // Addition & Subtraction
Addition and subtraction within 1000Add and subtract within 1000 using concrete models, drawings, and strategies based on place value; understand composing and decomposing tens and hundreds
Ages 7 to 8MethodMathematics // Addition & Subtraction
Adding and subtracting (age 7+)Add and subtract numbers with up to three digits using formal written methods of columnar addition and subtraction
Ages 7 to 8MethodMathematics // Addition & Subtraction
Estimating by roundingEstimate the answer to a calculation and use inverse operations to check answers; apply to increasingly large numbers using rounding and inverse reasoning
Ages 7 to 9Thinking skillMathematics // Addition & Subtraction
Missing number problems (age 7+)Solve addition and subtraction problems including missing-number problems, using number facts, place value, and more complex methods
Ages 7 to 8MethodMathematics // Addition & Subtraction
Two-Step Word ProblemsSolve one- and two-step word problems within 100 using addition and subtraction, with unknowns in all positions
Ages 7 to 8MethodMathematics // Addition & Subtraction
Addition and subtraction strategies (age 7+)Explain why addition and subtraction strategies work, using place value and the properties of operations
Ages 7 to 8Thinking skillMathematics // Addition & Subtraction
Numbers on a number lineRepresent whole numbers as lengths on a number line and represent sums and differences within 100 on a number line diagram
Ages 7 to 8RepresentationMathematics // Addition & Subtraction
Mental addition and subtraction (age 7+)Mentally add and subtract a three-digit number and ones
Ages 7 to 8MethodMathematics // Addition & Subtraction
Adding numbersAdd up to four two-digit numbers using strategies based on place value and properties of operations
Ages 7 to 8MethodMathematics // Addition & Subtraction
Mentally adding hundreds to 3-digit numbersMentally add and subtract a three-digit number and hundreds
Ages 7 to 8MethodMathematics // Addition & Subtraction
Mentally adding tens to 3-digit numbersMentally add and subtract a three-digit number and tens
Ages 7 to 8MethodMathematics // Counting & Cardinality
One-to-one countingOne-to-one correspondence when counting objects: each object is paired with exactly one number name
Ages 4 to 6ConceptMathematics // Counting & Cardinality
How Many in Total?Cardinality principle: the last number said when counting a set tells how many objects are in the set, regardless of arrangement or order counted
Ages 4 to 6ConceptMathematics // Counting & Cardinality
Comparing groups: more or fewerCompare two groups of objects to determine which has more, fewer, or whether they are equal, using matching and counting strategies
Ages 4 to 6ConceptMathematics // Counting & Cardinality
Representing numbers with objectsRepresent numbers using objects, pictorial representations, and the number line
Ages 4 to 6RepresentationMathematics // Counting & Cardinality
One More Each TimeEach successive counting number represents a quantity that is one larger than the previous number
Ages 4 to 6ConceptMathematics // Counting & Cardinality
Rote counting to 100Rote count forwards and backwards from 0 to 100, beginning from 0, 1, or any given number, by ones
Ages 5 to 6MethodMathematics // Counting & Cardinality
Counting in 2sCount in multiples of 2, 5, and 10 (skip counting)
Ages 5 to 7Method