Second grade math

Find here many important second grade math concepts taught in second grade. Teachers, parents, and math tutors can also use them as a guideline to illustrate a math lesson or to teach important skills that kids are supposed to know in second grade math.

Doubles

In doubles, both addends are the same.

1 + 1 = 2 2 + 2 = 4
3 + 3 = 6 4 + 4 = 8
5 + 5 = 10 6 + 6 = 12

Decompose a number

Equal groups

Groups have the same number of items.

Estimate:

No need to get an exact answer.

Possible answer: 35, 40 or 30

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a.m.	12:00 a.m. : midnight. sleeping time 7:30 a.m. : half past 7. wake up time 10:15 a.m.: a quarter after 10. doing work in class.

Example of angle.

When two lines meet at a common point, they make an angle.

Bar graph

A graph that uses rectangles to compare data. Saturday got 15 votes

Array

The array on the right is made with triangles. The array has 4 rows and 5 columns. 4 × 5 = 20 triangles

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Array

The array on the right is made with triangles. The array has 4 rows and 5 columns. 4 × 5 = 20 triangles

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Associative property

8 + 5 + 2 = (8 + 5) + 2
= 8 + (5 + 2)

Associative property

8 + 5 + 2 = (8 + 5) + 2
= 8 + (5 + 2)

Even number

There are 10 balls and 10 is an even number. An even number has 2 equal parts. 10 has 2 equal parts. Each part is equal to 5.

Count back

7 - 4

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Count back

7 - 4

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1 Dollar

1 dollar = 100 cents

Number line

Word form of number

345: three hundred, forty-five
268: two hundred sixty-eight

Odd number

There are 9 balls and 9 is an odd number. An odd number does not have 2 equal parts. One part is is 5 and the other is 4.

Quadrilaterals

Quadrilaterals are closed figures with 4 straight sides.

Standard form

A familiar way of writing numbers using digits

432

Tens

1 long is a physical representation of 10

Vertex

A point where 2 or more sides of shape meet. The vertex is the cube on the right is shown with a small white circle. The vertex of the triangle is shown with a small red circle.

Fourths

The parts that we get when something is divided into 4 equal parts.

p.m.	12:00 p.m. : noon. lunch time 3:30 p.m. : half past 3. nap time 6:45 p.m.: a quarter to 7. dinner time

Line plot

A line plot shows data on a number line using x or some other marks to show how many times a number appears. The number 6 appears 3 times.

Equation

4 + 8 = 12

14 = 6 + 8

Equation

4 + 8 = 12

14 = 6 + 8

Compare

4 is smaller than 8 or 4 < 8

8 is bigger than 4 or 8 > 4

Compare

4 is smaller than 8 or 4 < 8

8 is bigger than 4 or 8 > 4

Centimeter ruler

Centimeter or cm
1 meter = 100 centimeters
The length of a baseball bat is about 1 meter
The width of a finger or the diamater of a wedding ring is about 1 centimeter long