# 6.EE.A.1,2 Introduction to Expressions

```SCUSD Common Core Mathematics Lesson Planning Guide
Unit Title: Expressions
Approx. time:
Lesson: 1. Introduction to Expressions
50 minutes
A. Focus and Coherence
Students will know…
Vocabulary that represents the parts of an expression:
sum, product, factor, quotient, variable, constant and
coefficient.
That a variable is an unknown term (number) represented
by a letter.
Whole number exponents and variable exponents.
CCSS-M Standards: 6.EE.1, 6.EE.2
B. Evidence of Math Practices
What will students produce when they are making sense,
persevering, attending to precision and/or modeling, in
relation to the focus of the lesson?
Student will:
Be able to read, write and explain simple
algebraic expressions.
Explain the difference between a numerical
and an algebraic expression and why one may
be preferable to another in solving a problem.
Students will be able to…
Identify parts of an expression using mathematical terms
Read expressions with variables, whole numbers and
exponents
Student prior knowledge:
An ability to add, subtract, multiply and divide integers.
Arithmetic vocabulary including sum, product, factor,
quotient
Which math concepts will this lesson lead to?
Application of properties and order of
operations to algebraic expressions.
Guiding Question(s)
What is an expression and how/what does it represent?
What makes variables useful, powerful mathematical tools?
When do we use expressions with variables?
Unit: Expressions
Lesson: 1
Formative Assessments Ticket out the door
Read these algebraic expressions and write them in plain English.
4x + 5
3(m)
14m - 67
Write these in an algebraic expressions and explain
1. Fifteen less than twice a number
2. Three times a number increased by seventeen
3. The product of nine and a number decreased by six
Jennie earns \$30 a day working at a supermarket. Write an algebraic expression that will represent the amount of
money she will earn in d days.
What does n2+ 4 mean compared to n+ 82? Explain why you think they are the same or different.
Circle the variable, underline the coefficient and draw a triangle over the constant in this expression 3k -4
Anticipated Student Preconceptions/Misconceptions
Students may think the expression 5m where m=4 is 54 not 5x4.
Students may confuse what the variable represents.
Students might think that 16 g + 4 = 20 g or that 12m – 7 = 5
Materials/Resources
Whiteboards and markers, chapter resource masters for Glencoe chapter 3
C. Rigor: fluency, deep understanding, application and dual intensity
What are the learning experiences that provide for rigor? What are the learning experiences that provide for evidence of
the Math Practices? (Detailed Lesson Plan)
Warm Up
What is the product of 17 and 85?
If a truck carries four crates and each crate contains 1567 pounds of tomatoes, how could you find the total amount of
tomatoes? Explain using a complete sentence(s).
3 + 5 = 5 + ___
Unit: Expressions
Lesson: 1
Lesson
Explain to students that a number or
Explain to the students that you have found that on average, students use 2 reams of paper a
piece and I use 10 reams for my own use. I can write this mathematically as a variable
expression 2s + 10 to represent the amount of paper I need for the year. S is a variable that I
use to represent ____? And what does that coefficient 2 represent? How about the constant
10?
Try this in your group, if J represents the number of hours Julio works, and we know he is paid
\$10 per hour plus a bonus of \$25 for coming in on a Saturday. How could I write a variable
expression to show how much he earned Saturday (assume he worked at least one hour)
What might \$12J + \$25 indicate happened to Julio?
What we just learned.
Parts of an Expression
So people can talk about expressions, there are names for different parts (better than saying
&quot;that thingy there&quot;!)
Here we have an expression that says 4x - 7,
Variable :
not l, I, or o.
A symbol for a number we don’t know yet. It is usually a letter (but
Constant :
A number on its own.
Coefficient :
A number used to multiply a coefficient.
Operator :
A symbol (such as +, &times;, etc) that represents an operation
Term :
A Term is either a single number or a variable, or numbers and variables
multiplied together.
Expression
- signs)
A number, a variable or a group of terms (the terms are separated by + or
So, now we can say things like &quot;that expression has only two terms&quot;, or &quot;the second term is a
constant&quot;, or even &quot;are you sure the coefficient is really 4?&quot;
Exponents
IF 8 2 means 8 x 8 what would 75 mean? What would n3 mean?
Unit: Expressions
Lesson: 1
Exponents:
The exponent (such as the 2 in x2) says how many times to use the value in a multiplication.
Examples:
82 = 8 &times; 8 = 64
Y3 = y &times; y &times; y
Y2z = y &times; y &times; z
Exponents make it easier to write and use many multiplications
Example: y4z2 is easier than y &times; y &times; y &times; y &times; z &times; z, or even yyyyzz
Closure
See ticket out the door and use white boards or preprinted quiz sheet.
Suggested Homework/Independent Practice
See worksheet
3-1 Skills practice 1-16
3-1 Word problems 1-4