Deciphering Word Problems to Write Equations

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Objective

SWBAT write equations using real-life word problems.

Big Idea

Knowing the language of word problems helps students write equations which is a skill used in Algebra.

DO NOW

10 minutes

For the DO NOW, I have chosen 4 equations for the students to solve.  Each equation involves one of the 4 operations. Students should use their knowledge of solving equations to, independently, work on these problems.  Students should also check their solutions to prove that their answer is correct. (SMP 3:  justifying your answer).

Tools:  do now equations.

Apples in the Basket

15 minutes

Students will be given the following scenario along with paper apples to use as a manipulative. (SMP 5:  using tools to solve math problems.)Students can work in pairs or groups, but not individually.  I want students to have immediate conversation about their thoughts on how to solve.

Scenario:

George had a basket containing an even number of apples. He gives half to his brother and 3 to his mom.  How many apples did he have left?

Give students the paper apples as a manipulative and allow them time to sort through this problem.  At this time, there is no solution so you should expect to see a variety of different answers. Ask students why there are so many different answers?  What could we do to only get one solution.  Students should be able to say that providing them with the information on how many George had left over would help.

Then say, George had ended up with 4 apples.  Allow students to manipulate this equation with their paper apples.  Ask the students, “how many apples did George have to start with?”

Explain to students that by looking for key words and understanding missing information allows us to write equations to represent situations. 

Tools:  Apple manipulatives

Deciphering Word Problems to Write Equations

25 minutes

I’ve chosen 4 , one-step word problems to model with the students on how to get important information from the problem and then turning it in to an equation.  This part of the instruction exemplifies MP 2 and 4.  Students will need to understanding the meaning of the words and change them in to numbers or variables(SMP2).  Students will find the key words and use an equation to represent the word problem (SMP 4).

For each problem, I’ve set up a chart to help students organize the information from the word problem (SMP 5).  As we read through each problem, the students will be writing down what they know, what they need to know, key words, and finally the equation.  I’m not concerned with the students solving the equations, but if time permits, have them go back and solve each equation.  The main purpose for this lesson is to get students to pull out the important information, find the variable, and write the equation.  Students may struggle with writing the expression with the variable.  The chart will help them see what the variable represents and also what operation to use along with the variable.

I’m going to go through each problem with the students.  I will be asking them to find the information from the word problem.  This will be a guided practice with input from the students.  The chart will take you through what types of questions to ask.

Tools:  4 word problems with charts

Writing Equations Roundtable

20 minutes

Now it’s time for the students to perform independently.  I chose roundtable because students will work independently, at first, and then they can get some coaching from a tablemate if needed. There are 6 problems for the students to complete.  Each word problem represents a one-step equation.  If students are struggling, remind them they can use a chart to help them sort out the information.  The only problems that students typically have with these are the ones that require them to divide.  They need to pay attention to how many people the bill needs to be split into.  These little details can be ironed out if students continue to use the chart.

The roundtable activity supports MP 3 as students will be checking each other’s work and providing feedback when needed.

Tool:  Writing equations roundtable

Closure

15 minutes

The students will be completing a comprehension menu.  This activity allows students to work on problems that require mastery, understanding, self-expression and interpersonal responses.  Each part of the quad has them answer questions about equations.  Students should work independently.  They can share responses if time permits. Students should turn this in as evidence of student learning.

The comprehension menu supports mathematical practices:

SMP1: making sense of problems and looking for entry points.

SMP2: making sense of relationships among different mathematics concepts

SMP5: using tools strategically

Tools:  Comprehension Menu