What's

**new**in math?

__Understanding, Representing, and Solving Addition and Subtraction within 20__

In this unit, students add and and subtract within 20 using a variety of strategies and solve problems in that range. They develop a deeper understanding of the relationship between addition and subtraction.

**Common Core Focus:**

• Use addition and subtraction within 20 to solve word problems by using objects, drawing and equations with symbols for the unknown number to represent the problem.

• Apply the commutative property/turn-around facts to add. For example, use 8+3=11 to solve 3+8=?.

• Understand subtraction as an unknown addend problem. For example, subtract 10-8 by thinking 8+?=10.

• Use fact families to solve other facts. For example, if you know 7+8=15, then you know 15-8=, 15-7, and 8+7.

• Add and subtract within 20 using multiple efficient strategies such as: counting on, making ten, relating addition to subtraction, etc.

• Understand the meaning of the equal sign involving addition and subtraction. For example, 6+3=9, is the same as 9=6+3.

**What's ahead in math?**

In this unit students will solve word problems involving situations of adding to, taking from, putting together, taking apart, and comparing numbers. Students will determine if equations involving addition and subtraction are true or false. Students will add three numbers. Students will add and subtract within 20, demonstrating fluency within 10.

__Solving Addition and Subtraction Problem Types within 20__In this unit students will solve word problems involving situations of adding to, taking from, putting together, taking apart, and comparing numbers. Students will determine if equations involving addition and subtraction are true or false. Students will add three numbers. Students will add and subtract within 20, demonstrating fluency within 10.

Addition and Subtraction within 10

The children are learning strategies to help them solve addition and subtraction problems within 10. By the end of first grade, children should be able solve all problems within 10 in three seconds a problem. In order to help the children learn how to do this, the problems are broken down in strategies. You may have hear your child use the words: "ten friend" , "double", or "counting on". Below is a description of each strategy the children are learning:

Count on 1, 2, 3:

When adding two numbers, put the larger number in your head and count on 1, 2, or 3. You may have to change the order of the addends to do this. 6+3=(6... 7, 8, 9), 2+7=(7...8,9)

Count Back 1, 2, 3:

Put the whole in your head and count back. 9-2= (9...8,7)

Count On "Think Addition" :

When subtracting and the numbers are close start with the small number and count on to the large number to get the difference.. 9-7= (7...8,9 your answer is 2)

Doubles:

Adding a number to itself. 2+2=, 4+4=, also knowing if 4+4=8, then 8-4=4.

Near Doubles or Doubles +1:

When adding two numbers that are one apart (or number neighbors) double the small number and add one to the answer. 4+3=, double the 3 and add 1 to the answer. 3+3=6, so 4+3=7.

Ten Friends:

Two numbers when added together equal 10. 4+6=10, 8+2=10

Also knowing when 10 is the whole and you take away a part, the missing part is the ten friend. 10-7=3.

Below are addition and subtraction strategy flashcards. Some strategies will be introduced as we move on in the year. Feel free to copy at your convenience!

**addition_strategies.pdf**

**subtraction_strategies.pdf**

What is

Children work with a partner to play a math game.

Children work independently to solve word problems in their math journals.

Children work with technology to practice their fluency with math facts.

Children work with place value activities.

Children practice skills reinforcing what they have already been taught.

**B.U.I.L.D.**?**B.U.I.L.D**. is embedded into our math workshop.**B = Buddy Games**Children work with a partner to play a math game.

**U = sUper Problem Solving**Children work independently to solve word problems in their math journals.

**I = I-Pad/Computer**Children work with technology to practice their fluency with math facts.

**L = Learning About Numbers**Children work with place value activities.

**D = Doing Math**Children practice skills reinforcing what they have already been taught.