Learning Resource Type

Learning Activity

Fraction Equivalence: Let's Go Shopping

Subject Area

Mathematics

Grade(s)

4

Overview

Students will go on a “shopping trip” to buy items with prices written both as decimals and fractions with 10 or 100 as the denominator.  After they have decided which five items to “buy,” they will calculate the total cost of their items by adding fractions with 10 and 100 as the denominator.  The students will use a visual model to represent the equivalence between fractions with different denominators.

 

This activity results from the ALEX Resource Development Summit.

    Mathematics (2019) Grade(s): 4

    MA19.4.17

    Express, model, and explain the equivalence between fractions with denominators of 10 and 100.

    Unpacked Content

    UP:MA19.4.17

    Vocabulary

    • Equivalence
    • Denominator
    • Fraction model
    • Tenths
    • Hundredths
    • Sum

    Knowledge

    Students know:
    • Strategies for generating equivalent fractions.
    • Strategies for adding fractions with like denominators.

    Skills

    Students are able to:
    • Express a fraction with a denominator of 10 as an equivalent fraction with a denominator of 100.
    • Use models to illustrate equivalency between fractions with denominators of 10 and 100.
    • Explain equivalency between fractions with denominators of 10 and 100.
    • Use equivalency to add two fractions with denominators of 10 and 100.

    Understanding

    Students understand that:
    • equivalent fractions are fractions that represent equal value.

    Phase

    During/Explore/Explain
    Learning Objectives

    Learning Objectives

    Students will be able to add fractions with denominators of 10 and 100 using models or by making equivalent fractions.

    Activity Details

    • Before the lesson, set up the "store" by placing the items for sale around the room.
    • Explain that the students will be going on a shopping trip.  They will be able to “purchase” five items from around the room.  If they see something they would like to buy, they will write down the information for the item on their “Shopping Cart” sheet.
    • Before students begin shopping, model how to fill out the shopping cart sheet so that students know what information to record. Encourage students to browse a little first before choosing an item, because they only have five slots in their shopping cart.  You can also set some ground rules if you choose -- you can only buy an item once, you have to buy exactly five items, you have to buy one food/drink item, etc.
    • Allow students to walk around the room and shop, choosing items to buy and recording the fractional cost on their shopping cart sheet.  You may want to set a timer to help keep the students focused.
    • After students have finished shopping, they should return to their seat to calculate the total amount that they spent.  They can shade in the squares on the bottom of their sheet to help represent the equivalence between tenths and hundredths.
    • As students are working, ask them how much money each hundred-square grid represents.  How much does one square in the grid represent?  How much is one row or column? (Each grid is one dollar, the squares are one cent and the rows are ten cents.)
    • If time allows, figure out which student spent the most and which student spent the least.
    Assessment Strategies

    Assessment Strategies

    Check for accuracy with the students’ shopping totals.  Observe to see if students are combining tenths and hundredths appropriately.  A common misconception to look for is that adding 2/10 and 4/100 will equal 6/10 or 6/100 instead of 24/100.

    Variation Tips

    • You can change the pictures on the cards for sale to match what your students would want to buy.  
    • You can let students go on a second shopping trip and buy more than five items.
    • You can give students a challenge -- spend as close as you can to one dollar, spend less/more than their first trip, etc.

    Background and Preparation

    Background / Preparation

    • You will need to print and laminate the “Items for Sale” cards and place them around the room.  (You can print the cards two pages per sheet to conserve ink.  You can also use the digital version of the cards for distance learning.)
    • Each student will need a copy of the “Shopping Cart” sheet.

    Digital Tools / Resources

    ALSDE LOGO