A 60-minute lesson in which students will multiply decimals by whole numbers.
Present the following scenario to the students: You are having a sleepover with four of your friends. For dinner, you are ordering pizzas. You need to order five pizzas altogether; each pizza costs $12.80. What calculation will you need to do to work out the total cost of the pizzas?
Discuss the steps involved in multiplying decimal numbers by whole numbers, as outlined on slide 19 of the Operations with Decimals PowerPoint. Highlight the fact that, unlike adding and subtracting decimals, the decimal points do not need to be aligned.
Display and discuss the annotated examples of multiplying decimal numbers by whole numbers on slides 20-21. Highlight the importance of aligning the whole number to the right of the calculation.
As a class, use this process to work out the total cost of the pizzas in the tuning in scenario ($63.00).
Provide the students with a copy of the Multiplying with Decimals – Bingo Game. Read through the instructions on the game board as a class and answer any questions the students may have. Explain to the students that they will need to cut out the whole number cards and decimal number cards before starting the game.
Monitor and support the students as they play the bingo game in pairs. Students may wish to play the game more than once.
In order to review the content of the lesson, play a game of School Canteen: Restockon the ABC Splash website. This could be played as a whole class on the interactive whiteboard, or individually (depending on computer access).
Encourage more confident students to work together in pairs during the bingo game.
Allow less confident students to play the bingo game in a smaller group with the support of a teacher or teacher aide.
Suggested Assessment Strategies
used strategic whole class or individual questioning
observed student participation during learning activities
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