Math 1st Nine weeks

Our Focus

In the 1st nine weeks your student will be learning how to represent and solve single and multi-step addition and subtraction word problems within 1,000. The strategies used for computations will be based on place value, properties of operations, and the relationship between addition and subtraction. The methods for representation will include pictorial models, number lines, and equations. Students will also be using estimation as a strategy for problem solving and understanding reasonableness of their solutions.

Instructional Approach

Third grade students will be applying basic addition and subtraction facts as they solve more complex problems. Students will develop an understanding of the meanings of addition and subtraction of whole numbers by using models and problem solving. They will compare solution strategies to gain a deeper understanding of the relationship between addition and subtraction. Students will learn the traditional algorithm in 4th grade.

Family Support

You can help your child in several ways.

• Ask your child, “How is addition different from subtraction?”
• “Can you show me how addition looks on a number line/equation/strip diagram?”
• “Can you show me how subtraction looks on a number line/equation/strip diagram?”
• Encourage your child to practice his/her math facts at home. This will be critical to his/her success with fluently solving complex problems.
• Explore and discuss the key terms in the box below.

Sincerely,

The Third Grade Math Team

Important Vocabulary for this Unit

Addend - a number that is added to another

Sum - the result of adding two or more addends together

Addend + Addend = Sum

Difference - the result of subtracting one number from another.

Estimation- round

Expression - Numbers, symbols and operators (such as + and ×) grouped together that show the value of something. Example: 2×3 is an expression

subtrahend - The number that is to be subtracted. The second number in a subtraction. minuend − subtrahend = difference Example: in 8 − 3 = 5, 3 is the subtrahend.

minuend - The first number in a subtraction. The number from which another number (the Subtrahend) is to be subtracted. minuend − subtrahend = difference Example: in 8 − 3 = 5, 8 is the minuend.

difference - The result of subtracting one number from another. How much one number differs from another. Example: The difference between 8 and 3 is 5.

perimeter - The distance around a two-dimensional shape. Example: the perimeter of this rectangle is 3+7+3+7 = 20

polygon- A plane shape (two-dimensional) with straight sides. Examples: triangles, rectangles and pentagons. (Note: a circle is not a polygon because it has a curved side)

hour - A period of time equal to 1/24 (a twenty-fourth) of a day. 1 Day = 24 Hours 1 Hour = 60 minutes. Example: The amount of time between 5:00 and 6:00 is one hour.

event- A single result of an experiment Example Events: Rolling a "7" with dice is an event or Getting a Tail when tossing a coin is an event An event can include one or more possible outcomes: Choosing a "King" from a deck of cards is an event or Rolling an "even number" (2, 4 or 6) is also an event

interval- What is between two points or values. Examples: 1) All the numbers between two specific values (such as between 2 and 4) 2)A definite length of time marked by a start and finish 3) A line with definite end points (called a "Line Segment")

minute- A unit of time equal to 60 seconds. There are 60 minutes in an hour. Example: 10:35 means 35 minutes past 10 o'clock. (Note: for angles a minute equals 1/60th of a degree.)