Party Planning with Decimals
Students will be able to round decimal prices to the nearest dollar and calculate a total.
- Tell students that today they are going to plan the next class celebration. They will need to select desired supplies for the celebration from catalogs or websites while staying within a given budget.
- Tell them that Rounding, or altering a number to make it less exact but more convenient, the decimal places will make it easier for them to see if they have stayed within budget.
- Show students a party supply catalog or website. Tell students their maximum budget.
Explicit Instruction/Teacher modeling(5 minutes)
- Fold a piece of paper so it has three columns. Label these columns "Product," "Price," and "Rounded Price."
- Select a party product from the catalog or website.
- After recording the product and price, review with students how to round a decimal to the nearest whole number.
- Review the rules for rounding up or down.
Guided practise(10 minutes)
- Have students take turns selecting a product for you to record.
- Ask students to round the decimal price to the nearest dollar and explain the rule they used.
- After recording three products, demonstrate finding the total price using the rounded whole numbers.
- Ask students why they think rounding the decimal prices makes it easier to find the total price.
Independent working time(20 minutes)
- Give small groups of students a piece of lined paper for recording their desired purchases. Have them write the type of celebration and the budget at the top.
- Have them create the same three columns you created earlier: "Product," "Price," and "Rounded Price."
- Provide each group with a party supply catalog or access to a party supply website.
- As students select products, circulate among the groups to check for correct rounding and reminding them of their budget.
- Enrichment:Students will be able to calculate shipping charges for the total amount of their purchase. Once a group has reached a total price for their desired products, have them locate the shipping charge chart and calculate the shipping charge and new total price.
- Support:Scaffold the choice process by requiring students to choose 1 decoration, 1 paper product and 1 activity. Give students number lines to help them with rounding.
- While circulating among groups, ask individuals to explain why a certain price was rounded up or down. Record these observational notes to plan for next instructional steps.
- Evaluate each student's ability to correctly round decimal prices to the nearest whole dollar.
Review and closing(5 minutes)
- Ask students what problems they encountered while planning.
- Ask them how rounding the prices made it easier for them to keep a running total and stay within budget.