Getting Started 
Misconception/Error The student writes an expression or an equation that has no meaning in the context of the problem. 
Examples of Student Work at this Level The student writes an expression such as 56(2x + 1)
The student writes an equation such as 2x + y = 56

Questions Eliciting Thinking What does the expression 2x + 1 represent in this problem?
What does 56 represent in this problem?
How do you find the perimeter of a square? 
Instructional Implications Work with the student on modeling relationships among quantities with equations. Begin with situations that can be modeled by equations of the form x + p = q and px = q (6.EE.2.7). Then progress to situations leading to equations of the form px + q = r and p(x + q) = r. Emphasize the relationship between algebraic expressions and the quantities they represent in the context of the situations in which they arise. For example, if 2x + 1 represents the length of a side of a square then explain to the student that 4(2x + 1) represents the perimeter of the square. If the perimeter is numerically equal to 56, then 4(2x + 1) is equal to 56 which gives rise to the equation 4(2x + 1) = 56.
If necessary, review solving equations of the form x + p = q and px = q (6.EE.2.7) and equations of the form px + q = r and p(x + q) = r. Provide additional opportunities to solve word problems by writing and solving equations of the form x + p = q, px = q, px + q = r, and p(x + q) = r, where p, q, and r are specific rational numbers. 
Moving Forward 
Misconception/Error The student writes an equation that contains significant errors. 
Examples of Student Work at this Level The student writes the equation as 2x + 1 = 56.
The student writes an equation that ostensibly shows how to calculate x rather than one that directly models the relationship among the quantities in the problem.

Questions Eliciting Thinking How many sides does a square have? How do you find the perimeter of a square?
What does 2x + 1 represent in this problem? Does it represent the perimeter of the square?
How are 2x + 1 and 56 related? Can you write an equation that shows this relationship? 
Instructional Implications Review the concept of perimeter and the definition of square. Guide the student through the process of writing an appropriate equation that directly models the relationship between the length of a side of the square, 2x + 1, and the perimeter of the square, 56. Provide additional properties to write and solve equations in order to solve problems in geometric contexts involving perimeter and area.
If necessary, review solving equations of the form px + q = r and p(x + q) = r. Provide additional opportunities to solve word problems by writing and solving equations of the form px + q = r and p(x + q) = r, where p, q, and r are specific rational numbers. 
Almost There 
Misconception/Error The student writes a correct equation but makes an error in solving the equation or in calculating the length of the side of the square. 
Examples of Student Work at this Level The student makes a division error in the equation solving process.
Â Â Â
The student says the length of the side is the same as the value of x, 6.5.

Questions Eliciting Thinking I think you may have made an error in solving your equation. Can you check your work?
How can you check your solution? 
Instructional Implications Provide direct feedback on any errors that the student might have made and allow the student to correct them. Review solving equations of the form px + q = r and p(x + q) = r. Provide additional opportunities to solve word problems by writing and solving equations of the form px + q = r and p(x + q) = r, where p, q, and r are specific rational numbers. 
Got It 
Misconception/Error The student provides complete and correct responses to all components of the task. 
Examples of Student Work at this Level The student writes the equation as 4(2x + 1) = 56 and correctly solves the equation getting x = 6.5. The student calculates the length of the side of the square as 2(6.5) +1 = 14.

Questions Eliciting Thinking Can you solve your equation by first dividing each side by four (if the student initially used the Distributive Property)?
Can you solve your equation by using the Distributive Property (if the student initially divided each side of the equation by four)?
Does x have any meaning in this problem? What does x represent? 
Instructional Implications Challenge the student to describe an arithmetic solution to finding the value of x and to compare it to the algebraic solution used in solving his or her equation, identifying the sequence of operations used in each approach. Consider implementing MFAS task Algebra or Arithmetic? (7.EE.2.4). 