2ND GRADE MATHEMATICS

NUMBER AND OPERATIONS

 Count by 1s, 5s, and 10s

 Compare numbers with symbols

 Understanding place value up to 999

 Add/subtract numbers with missing values

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NUMBER AND OPERATIONS CONT.

 Understand multiplication with objects

 Understand division with multiplication

 Represent commonly used fractions

 Model fractions with folding strips

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COUNTING

 Starting from any number to 1000   1,2,…8,9,10   10,20,30,…70,80   100,200,…500,700,800

10

20

30

MATHEMATIC SYMBOLS

 < is less than  > is greater than  = is equal to or same  Alligator trick

  < or > is alligators mouth eating

20>5 38=38 78<96

67__76

43__23 HINT: which one would the gator eat?

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PLACE VALUES

 Ones place is last number

 Tens place is left of ones place

 Hundreds place is left of tens place

528 ones

tens

hundreds

62

tens

ones

PLACE VALUE EXAMPLES

 What number is in the hundreds place?   587 answer: ___   823 answer: ___

 What number is in the tens place?   709 answer: ___   16 answer: ___

 Write a number with:   a 6 in the tens place   9 in the hundreds place

Answer: ___

ADDITION

 Subtract given number from the solution

 Check   Add answer with

given number   Should be the solution

given

Find missing values Example

56+__=93

93 -56 37 CHECK

56+37=93

SUBTRACTION

 Subtract solution from the given value

 Check   Subtract new value

from given value   Should get the given

answer

Find missing values Example

43-__=12

43 -12 31

CHECK

43-31=12

ADDITION AND SUBTRACTION EXAMPLES

  73+___=90   Answer: ____

  13+___=57   Answer: ____

  43+___=59   Answer: ____

  56-___=12   Answer:____

  78-___=20   Answer:____

  39-___=9   Answer:____

Addition Subtraction

MULTIPLICATION

 Example 1.  3 groups of 4 2.  Add up each group 3.  Get answer 3 × 4 =12

GROUP 1

GROUP 2

GROUP 3

4+4+4=12

MULTIPLICATION EXAMPLES

5 × 3=__

2 × 9=__

8 × 4=__

DIVISION WITH MULTIPLICATION

 Division is multiplication backwards 1.  Take the answer from multiplication problem 2.  Divide it by a number in problem 3.  Should get other number in problem

2 × 4=8

8 ÷ 4=2

EXAMPLE

4+4=8

4 groups with 2 in each

Total of 8

DIVISION EXAMPLES

  9÷3=__

  Make 3 groups   Put a circle in each until you reach 9   Answer=3

  3 in each box

  20÷5=__

Answer=4

MULTIPLICATION AND DIVISION EXAMPLES

  14×2=___

  15×3=___

  7×3=___

  80÷10=___

  45÷9=___

  24÷3=___

Multiplication Division

FRACTIONS

 Filled in strips numerator (top number)  Total number of strips denominator (bottom

number)

  ½=one half

  ⅓=one third

 ¼=one fourth