AR Remediation Plan – Algebraic Expressions
Evaluating Algebraic Expressions
STRAND: Patterns, Functions, and Algebra
STRAND CONCEPT: Algebraic Expressions
SOL 7.11, 8.14a
Remediation Plan Summary
Students evaluate algebraic expressions, using physical representations of numbers as replacement values of
variables.
Common Errors and Misconceptions
Students may substitute the incorrect value in for the variable when there are two variables in the
algebraic expression.
Students may forget to follow the order of operations.
Students may be confused when substituting in a negative value into an expression and should be
reminded to put the value in parentheses.
Materials
Warm Up activity sheet
Large number cards
Evaluating Expression Practice sheet
Tape
Introductory Activity
Have students complete the “Warm-up” worksheet. Once they have completed the task, review the solutions,
and answer any questions they may have. Engage students in a discussion of why the order of operations is
important in mathematics.
Plan for Instruction
1. Cut apart the attached number sheets so that each large-sized number is on one sheet.
2. Write the expression
2 3 8x
on the board. Tell students that the variable, x, in this expression can
have many different values and that you are going to replace the x with a number. Tape one of the large
numbers over the x, and evaluate the expression on the board asking for student input.
3. Have students choose several different values for x from the number sheets. Give each student a different
number (other than the first one you used as a class) and ask them to evaluate the expression with their
number. After students have evaluated their expression and ask them to trade papers with a partner. Ask
each partner to rework the problem and verify the answer. Then, show the evaluation of several
expression on the board and discuss how the order of operations was applied.
4. Write the expression
4 2 • 3ab
on the board. Have two students come up to the board. Have the first
student choose a value for a from the number sheets and the other choose a value for b. Have the
students tape their chosen numbers in the appropriate places over a and b. What do you notice about the
expression now? Ask students to solve the problem and once the class is done, ask students for the
answer. Have students explain their process and keep a list of answers provided. Students may incorrectly
interpret
43
as 43 and
4 5
as
45
. Explain that the substituted numbers must be enclosed in
parentheses in order for the side-by-side digits to indicate multiplication.
