# ALEX Learning Activity

## Burgers with a Side of Variables

A Learning Activity is a strategy a teacher chooses to actively engage students in learning a concept or skill using a digital tool/resource.

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This learning activity provided by:
 Author: Samantha Wallace System: Limestone County School: Cedar Hill Elementary School
General Activity Information
 Activity ID: 2446 Title: Burgers with a Side of Variables Digital Tool/Resource: Fast Food Variables Slide Web Address – URL: https://docs.google.com/presentation/d/1xcxxlO0uY89AA2lBs55hXIa6mphk45J3NEjd60K1vJU/edit?usp=sharing Overview: In this activity, students will be writing equations using variables that represent different food items.  They will develop the foundational understanding of variables being used as a symbol to represent a number.  They will also write expressions using variables and then evaluate the expressions at specific values for the variables.This activity was created as a result of the ALEX Resource Development Summit.
Associated Standards and Objectives
Content Standard(s):
 Mathematics MA2015 (2016) Grade: 6 13 ) Write, read, and evaluate expressions in which letters stand for numbers. [6-EE2] a. Write expressions that record operations with numbers and with letters standing for numbers. [6-EE2a] Example: Express the calculation, "Subtract y from 5," as 5 - y. b. Identify parts of an expression using mathematical terms (sum, term, product, factor, quotient, coefficient); view one or more parts of an expression as a single entity. [6-EE2b] Example: Describe the expression 2(8 + 7) as a product of two factors; view (8 + 7) as both a single entity and a sum of two terms. c. Evaluate expressions at specific values of their variables. Include expressions that arise from formulas used in real-world problems. Perform arithmetic operations, including those involving whole-number exponents, in the conventional order when there are no parentheses to specify a particular order (Order of Operations). [6-EE2c] Example: Use the formulas V = s3 and A = 6s2 to find the volume and surface area of a cube with sides of length s = 1/2. NAEP Framework NAEP Statement:: 4A3a: Use letters and symbols to represent an unknown quantity in a simple mathematical expression. NAEP Statement:: 4A3b: Express simple mathematical relationships using number sentences. Alabama Alternate Achievement Standards AAS Standard: M.AAS.6.13- Describe a given mathematical or real-world problem with an expression including one unknown. M.AAS.6.13a- Evaluate expressions at specific values of their variables (e.g., m + x = ?, where x = 3 and m = 2). M.AAS.6.13b- Identify parts of an expression using mathematical terms (e.g., sum, product, difference, quotient). Mathematics MA2015 (2016) Grade: 6 17 ) 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. [6-EE6] NAEP Framework NAEP Statement:: 8A4a: Solve linear equations or inequalities (e.g., ax + b = c or ax + b = cx + d or ax + b > c). NAEP Statement:: 8A4b: Interpret "=" as an equivalence between two expressions and use this interpretation to solve problems. Alabama Alternate Achievement Standards AAS Standard: M.AAS.6.17- Match a phrase to the corresponding one- step one-variable expression (e.g., "a number plus 3" matches "x + 3").
Learning Objectives:

Students will be able to use variables to represent numbers.

Students will be able to write expressions to solve real-world problems using variables.

Students will be able to evaluate expressions at specific values of their variables.

Strategies, Preparations and Variations
 Phase: Before/Engage Activity: Begin by explaining to the students that today they will be learning about how to use letters in math.  When we use a letter to represent a number in math, it is called a variable. If students are using math journals, they can write the word variable and define it.  Explain that it's more common to use lowercase letters for variables and that any letter can be used as a variable. Display the slide with the food images.  Ask a student to pick two items she might want to order.  For example, the student might choose a burger and a hotdog.  Write a lowercase "b" under the burger and a lowercase "h" under the hotdog.  Write the expression "b + h" and explain that this expression represents what the student ordered.  Continue this procedure, allowing students to pick items and write the expressions using the appropriate variables.Once students are comfortable with using the variables and writing expressions, explain that the students are going to see how we might apply this to the real world.  Assign each food item with a price and write the amounts under the pictures.  For example, under the burger, you should write "b = \$3".  Continue asking students to pick food items, but now they need to find the total cost of the meal.  Model the first two examples and then allow the students to work independently.  Make sure to write the equations with the variables and then a separate equation with the substituted amounts. Assessment Strategies: Evaluate student understanding through questioning during the activity.  Observe to see if students are able to use variables to write an expression to represent the meal they've ordered and if they can solve the equations by substituting the correct values for the variables.   At the end of the activity, you can place an order out loud for all of the students to solve independently as an exit ticket. For example, you might say, "I want to order 2 burgers, a hotdog, and a taco."  The students should write "b+b+h+t" and calculate the total price of the meal. Advanced Preparation: You will need a projector and board to display the slide.  To label the items and write the expressions, you can use a board with the appropriate technology or chart paper taped to the board.  You can also enlarge the images and then print and tape them to a dry erase board. Variation Tips (optional): Notes or Recommendations (optional):
Keywords and Search Tags
 Keywords and Search Tags: equation, expression, variable