Unit Title: Problem Solving Grade Level: 5
Lesson Title: Writing an equation to solve a word problem
Standards: 1, 2, & 3
By the end of this lesson, the students will be able to:
J Read and understand what a word problem is asking for
J Set up an equation with a variable
J Organize the information to fit into an equation
Solve for the variable
J Teacher prepared worksheets
Motivation: 10 minutes
Yesterday, my friend called me with a problem. She wanted to throw a party for her parents anniversary but did not know how much money it would cost. She figured out that there were 15 people, and that it would cost $20 per person. She started to explain to me that she was making a table so that she could add up the amount of money. I had not thought of figuring out the problem that way, which made me think of all the different ways that we can figure out word problems.
Ø Can you help me make a list of different strategies that I could have suggested to her?
· Guess and check
· Draw a picture
· Write an equation
· Make a list
· Make it simpler
· Get rid of excess info
· Draw a picture
· Act it out
· Make a table
· Look for patterns
Ø Today we are going to focus on a problem solving strategy called writing an
Ø By the end of this lesson you should be able to solve a word problem by using an
Developmental Activity 12 minutes
Ø Introduce the word variable (A quantity which may increase or decrease / The variable is the amount that we do not know)
Ø When we are solving an equation with a variable, we use an N to represent
the unknown variable.
Ø Can someone tell me what we should do when we see a word problem that we
know we have to solve with an equation?
· Read the problem carefully
· Re-read the problem
· Get rid of any extra information
· Figure out what they are asking for in the answer.
· Set up the equation
Ø When we are setting up an equation, it is important to understand what we are trying to find out. It is often helpful to write down the information that we have, and the information that we need.
Ø Example: Jon has 3 apples, Kim has 2 apples. How many apples do they have in all? John = 3, Kim = 2, Total = N
Joe has $5 and need to get $10. How much more money does he need?
Joe = $5, Total = $10, N = the amount of additional $ needed.
Ø Once you find your answer, it is important to go back and check to make sure that your answer makes sense.
Ø Can anyone tell me how we can check to make sure that our answer is correct?
Application Activity 10 minutes
Ø Start with easy examples, and have the students write the number sentence on the board. (see attached)
Ø Remind students to check and label their answers.
Ø Look and solve the problems in the textbook.
Ø Hand out a worksheet with problems that need to be answered. Remind students to show their work.
Ø Supply manipulatives for students who need them.
Ø I will take a group of students (Enrichment) into another classroom and work with them on more challenging problems.
Ø We will do some sample problems as a group, and then they will work on a teacher prepared worksheet. We will do one question at a time to prevent any student from being stumped on one question. I will be encouraging the students to explain any problem that a classmate does not understand.
Assessment 13 minutes
Ø Mrs. Weinstein will wrap-up the lesson with the class in her classroom. (This has been previously discussed with Mrs. Weinstein)
Ø I will assess the small group by having the students explain in detail the process that they went through to find their answers. I will probe the rest of the students to think of alternatives to answering the same problems. In addition, I will allow enough time for the students to ask questions before I jump in and question a student. This will allow for cooperative learning.
Ø We will compare the different thought processes that the students used to find their answers
Wrap-up 5 minutes
Ø Today we learned one of the harder problem solving strategies. This strategy can be very useful to you whether you realize it or not. The next time that you get a dollar to buy candy, you can figure out how many different pieces you can get by writing an equation. You can also use it when you are trying to manage enough time to get your homework done and play outside before it gets dark.
A follow up activity will be done next week involving problem solving. The children will each receive supermarket circulars from the newspaper. We will discuss the different ways that we can make word problems using the given information. The students will then have to come up with a word problem that involves the different items they have, and a specific amount of money that they are given. After they word problems are created, the children will switch and try to solve the problems. .