Date: December 15, 1998

Grade Level(s): 3, 4

Subject(s):

• Mathematics/Process Skills

Duration: Two 30-minute sessions

Description: The four steps method of problem solving provides a guide for students to follow in looking back. At each step students should lay down their pencils and ask a question or questions about what he/she has done. The students are constantly reflecting on the problem itself and assessing their work as they process it rather than looking back only after they have completed the problem.

Goals: To be able to solve problems successfully. This method will give them the ability to focus their attention on the steps in the solution rather than only the answer. Students should have mastered the multiplication, addition, and subtraction.

Objectives: Upon completion of this lesson, the student will be able to solve problems easily and quickly.

Materials:

• paper
• pencil

Step 1: Read the problem. What is the important information? What is the question? Visualize the situation. Restate the problem.

Step 2: Diagram or represent the problem. Does the diagram represent all the pertinent information? Is the data correct?

Before	After
20 marbles	15 marbles
80 grams	66 grams

What conclusion can you draw from the diagram? The difference between Before and After: 5 marbles and 14 grams.

Step 3: Set up the calculations and compute.

80	14	66
-66	x 3	-42
-----	-----	-----
14	42	24

Is the important data included and organized in the proper way? Are the computations correct?
"Yes, 80 and 66 are right; the difference is 14. That's what 5 marbles weigh, so 15 marbles would weigh 42 grams (3x14=42). Then the can weighs 66-42= 24 grams.

Step 4: Write the answer.
The can weighs 24 grams.
Have you answered the question? Does the answer make sense? Is there another way to check it?
"Well, 20 marbles alone would weigh 56 grams (4x14=56), and 80-56=24, so it must be right."