Halloween Repeated Addition and Multiplication
Students will practise writing addition and multiplication number sentences.
- Students will convert addition number sentences into multiplication number sentences.
- Ask students the following question and have them discuss it with a neighbour or table group: “If three black cats crossed your pat on Halloween night, and they each have four legs, how many legs crossed your path?” Challenge them think about how they could represent this as an addition and a multiplication problem. Share their thinking and their solutions as a class.
Explicit Instruction/Teacher modeling(5 minutes)
- Explain that students will be reviewing the concept of repeated addition and multiplication using Halloween images.
- If they need a refresher, explain that addition problems, when they involve the same number, can also be shown as multiplication.
- Write a few examples on the board, such as: 2 + 2 + 2 = 2 x 3 = 6 Two added three times is the same as 2 x 3 and both are equal to 6. You could also say three groups of two.
Guided practise(10 minutes)
- Now, using Halloween images, draw pictures that would accompany a repeated addition problem. Examples: Draw two spiders with 8 legs each Draw 5 ghosts with 3 holes cut in each sheet Draw 2 jack-o-lanterns with 4 teeth in each mouth Draw 6 bats, each with 2 wings
- Under each drawing, write a question that asks for the total amount of legs, holes, teeth, wings, etc.
- Write the addition problem, the multiplication problem and solution that go with each problem.
Independent working time(25 minutes)
- Distribute the 1” graph paper (one per student). This will help them keep their paper organized. They could put one image in each square.
- Instruct students to create three examples just as you modeled on the board including all 5 parts: picture, question, addition sentence, multiplication sentence.
- Put Halloween music on while students work independently.
- NOTE: Since some students might want to invest more time in the drawing than the maths, you could tell divide the amount of time they have to work by three and help them pace their work to be completed by the end of Independent Work Time.
- Have students work in pairs.
- Clearly label an example as you expect them to do it on the board, numbering each step 1-5.
- Have students use bigger numbers, up to two or three digit numbers (four bags of Halloween candy and each bag has 150 pieces in it)
- Have students use words to show their thinking (with labels and writing in the margins) how the addition problem translates into the multiplication problem. For example, “When there are three cats, and the each have two eyes, you can add two plus two plus two. Since you are adding three two’s together you could also count by two’s three times which is the same as 2 x 3”
- While students are working, or at the end, check to ensure that each student represents the image with the correct addition and multiplication problems.
Review and closing(10 minutes)
- Have students share one of their problems with the class or in a small group.