## Let's Go Shopping

### Carol SpiceSanta Rosa District Schools

#### Description

Excite your students! Give them \$500 to spend. Little will they know how much they are learning about fractions, decimals, and percents.

#### Objectives

The student knows the relationships among fractions, decimals, and percents.

The student solves real-world problems involving decimals and fractions using two- or three-step problems.

The student solves real-world problems involving percents (for example, discounts, simple interest, taxes, tips).

The student solves multi-step real-world problems involving whole numbers, fractions or decimals using appropriate methods of computation, such as mental computation, paper and pencil, and calculator.

#### Materials

- Worksheet (See associated file)

#### Preparations

1. Students should have some prior knowledge of the conversion of fractions to decimals and the multiplication of decimals.
2. Copy worksheets Part 1, 2, & 3 (one copy per student. I do 1 & 2 back to back.)

#### Procedures

Day 1: The time allotted for day one will depend on if you allow students to locate items and prices and fill out Part 1 in class or at home. I prefer not to take up class time for this part of the activity. I do the procedures for step one at the end of one period and allow students 3 or 4 days to gather information and complete Part 1.

1. Introduction: “Who likes to shop?” Open up a discussion about shopping; ask students what they would like to buy if they had \$500 to spend. Discuss prices, discounts, and sales tax.

2. Tell students that they have \$500 to spend any way they choose.

3. Pass out worksheet Part 1.

4. Explain how to fill out the worksheet, going over the directions at the top of the worksheet. Reinforce the concept of estimating the amounts to save time and computation.

5. Give students a due date to finish and bring in worksheet Part 1.

Day 2 (of activity): You may have a few days of instruction in between.
1. Have students get out worksheet Part 1 and circulate to insure the worksheet is complete.

2. Pass out worksheet Part 2.

3. Go over instruction 1, telling students to list the items they selected in the first column A, paying attention to which items are receiving a higher discount. Let students discover the best way to list the items.

4. Discuss instruction 2, reviewing how to convert fractions and percents to decimals. Give students several examples of each. I use examples from the students’ papers.

5. Instruct students to find all of the discounts in decimal form and then to follow instruction 3, taking the original amount from column A on Part 1.

6. Tell the students to go on to step 4 of the instructions.

7. Circulate and assist checking computations.

8. Discuss how students could estimate the amount of discount and how useful this is when shopping.

9. Review converting percents and fractions to decimals and how to find an amount of discount with pencil and paper, calculator, and mental math.

Day 3:
1. Review Parts 1 & 2.

2. Pass out worksheet Part 3.

3. Show students how the letters on worksheet 3 match the letters on worksheet 2.

4. Instruct students to fill in columns B & C and then to perform the operation and fill in column D.

5. Circulate and assist.

6. When most are finished, discuss the tax column, reviewing how to convert the percent to a decimal. Stress that the percent must be converted before multiplying. Have the students fill in the tax column with 7.5% in decimal form all of the way down.

7. Go over the rest of the steps in the instructions.

8. Circulate and assist, allowing students to finish the worksheet.

9. When most of the students are finished, discuss the bottom totals to find out who saved the most and lead the students to discover why that person saved the most.

10. Collect worksheets and evaluate for assessment.

#### Assessments

Formative assessment of prior knowledge and understanding will be done through class discussion and teacher questioning.
Each student will be assessed on the completion and computations on the worksheets. Students who are having difficulty can be paired with more knowledgeable student or can conference with the teacher.

#### Extensions

Students need prior knowledge of fraction and percent conversion to decimal and the multiplication of decimals.
This lesson could be done as a group activity.
Dollar amounts and number of items could be adjusted to fit students’ needs.

#### Attached Files

Worksheets Let's Go Shopping worksheets part 1, 2, & 3.     File Extension: pdf