CCSS.Math.Content.6.EE.B.6
The Standard
Use variables to represent numbers and write expressions when solving a real-world or mathematical problem; understand that a variable can represent an unknown number, or, depending on the purpose at hand, any number in a specified set.
Common Core State Standards for Mathematics · Expressions and Equations
Teacher's field guide
What This Standard Means
What Students Need to Do
- Students use letters to stand for numbers in mathematical and real-world situations. They write expressions and decide whether each variable represents one unknown number or any number from an allowed set.
What Mastery Looks Like
- Students choose a variable, state what it represents, and write an expression that matches the situation. They also explain whether the variable is one unknown value or can take several reasonable values.
Common Misconceptions
- Students may think a variable always stands for one fixed unknown, even when it represents any number in a set. They may turn phrases into expressions incorrectly, such as writing 5 - n for “5 less than n.”
How to Assess It
- Give this exit ticket: “A movie ticket costs $8. Write an expression for the cost of t tickets, and explain what values t can take.”
Lesson moves
Ways to Teach It
Give pairs bags of hidden counters, then have students write an expression for the total after adding four counters to each bag.
Ask students to compare “a number less than 12” and “12 less than a number,” then explain why the expressions differ.
Play a phrase-matching game using cards with verbal descriptions, variable expressions, and possible variable values.
Use a school store menu and have students write expressions for buying different quantities, including limits based on available money.
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Printable 6.EE.B.6 Worksheet
A ready-to-print activity worksheet aligned to CCSS.Math.Content.6.EE.B.6, with an answer key for the teacher on its own page. No account needed.
PDF, US Letter, prints cleanly in black and white.
Download the worksheetLearning progression
Where This Standard Sits
See the whole path on the Expressions & Equations progression map.
Before This Standard
If students are struggling here, check these first.
- CCSS.Math.Content.6.EE.A.2
Writing and interpreting expressions with letters is needed to model problem quantities using variables.
- CCSS.Math.Content.5.OA.A.2
Writing and interpreting number expressions supports translating situations into variable expressions and seeing variables as stand-ins for numbers.
- CCSS.Math.Content.4.OA.A.2
Using a symbol for an unknown in comparison problems supports later use of variables to represent unknowns in expressions and situations.
What This Unlocks
Mastery here sets students up for these next.
- CCSS.Math.Content.6.EE.B.7
Understanding variables as unknown numbers supports writing the simple equations needed before solving x + p = q and px = q.
- CCSS.Math.Content.7.EE.B.4a
Students must use variables for unknown quantities before writing and solving one-step or two-step equations from word problems.
- CCSS.Math.Content.7.EE.B.4
Representing unknown quantities with variables and expressions is essential before forming equations or inequalities from problem situations.
- CCSS.Math.Content.6.EE.C.9
Using variables for unknowns or varying values supports writing equations for related quantities and interpreting independent and dependent variables.
- CCSS.Math.Content.6.EE.B.8
Understanding a variable as any number in a set supports seeing x > c as a condition with many solutions.
Keep exploring
Related Standards
- CCSS.Math.Content.6.EE.A.2c
Evaluate expressions at specific values of their variables. Include expressions that arise from formulas used in real-world problems. Perform arithmetic operati...
- CCSS.Math.Content.7.EE.B
Solve real-life and mathematical problems using numerical and algebraic expressions and equations.
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