Students will use equal groups and repeated addition to understand the concept of multiplication.
Introduction (1 minutes)
- Tell students that today they will begin learning about multiplication.
- Tell students that multiplication can be thought of as repeated addition of equal groups.
Explicit Instruction/Teacher Modeling (9 minutes)
- Write an example multiplication problem on the board. For example: 4 x 3
- Tell your students that the x (multiplication sign) means the same thing as groups of. Explain this in the context of your example: This problem can be read as 4 groups of 3.
- Explain that in this equation, the numbers 4 and 3 are each known as a factor. Define factors as the numbers we can multiply together to get another number.
- Draw 4 circles and put 3 dots in each circle, to illustrate 4 groups of 3.
- Count each of the dots as a class. Once you're finished, write the entire equation on the board: 4 x 3 = 12
- Tell your students that the answer to a multiplication problem is known as the product.
- Explain to your class that multiplication problems can be represented as repeated addition of the same number. Using the white board, join the circles you drew with plus signs, and write an addition equation that matches your example multiplication problem. For example: 3 + 3 + 3 + 3 = 12.
- Discuss the benefits of multiplication (as opposed to addition) with your students. Some questions to ask include: Why do we multiply? When would it be easier to multiply instead of adding? Give an example to show when multiplication is easier than addition. For example: Write the problem 9 x 8 on the board, and write 8 + 8 + 8 + 8 + 8 + 8 + 8 + 8 + 8 on the board. Guide students in their thinking by asking, Which problem do you think would be faster to solve?
- Tell students that they will be using candy to figure out multiplication problems today.
- Using an interactive whiteboard, document camera, or projector, display the Candy Math Recording Sheet to the class.
- Discuss the example on the Recording sheet.
- Next, project the Equal Groups worksheet. Draw dots or candies to model solving the example problem for your students.
Guided Practice/Interactive Modeling (10 minutes)
- Pass out a copy of Equal Groups and a copy of Candy Math Recording to each student, along with a bag of candy.
- Write an example multiplication problem on the board, such as 4 x 5.
- Tell your students to make 4 groups of 5 by putting 5 candies each into 4 circles.
- Ask students to solve the equation by counting how many total candies they used.
- Once students have the answer, challenge them to solve this multiplication problem using repeated addition. To do this, they must count how many candies are in each circle, and add those numbers together. Students should produce 5 + 5 + 5 + 5.
- Guide students to write this information on their worksheet.
- Check to make sure students understand the relationship between multiplication, equal groups, and repeated addition by asking questions such as: How are multiplication and addition related? How can we use equal groups to solve a multiplication problem?
Independent Working Time (20 minutes)
- On the board write five more multiplication problems that students can work on at their own pace. For example: 3 x 6, 7 x 2, 2 x 4, 6 x 3, 8 x 3.
- Circulate around the classroom as students are working to monitor accuracy.
- Enrichment: Ask students if they see a relationship in the problems that they solved. Do they see any products that are the same? Students should be able to determine that 3 x 6 and 6 x 3 have the same product. Let students know that this is known as the commutative property of multiplication. Challenge students to figure out if this always works in multiplication. If we switch factors, will the product remain the same? Give students a few problems to try this with, such as: 4 x 3, 3 x 4; 2 x 5, 5 x 2; etc.
- Support: Gather students who need extra support into a small group, and model how to solve multiplication problems to 10, focusing mainly on repeated addition.
Assessment (9 minutes)
- Pass out a blank sheet of paper to each student.
- Write a multiplication problem on the board, such as 4 x 6.
- Ask students to solve the equation by drawing a picture to represent equal groups. Instruct them to include the related repeated addition problem.
- Check each student's work to ensure understanding.
Review and Closing (1 minutes)
- Tell students that today they learned two strategies that they can use to solve multiplication problems.
- Allow students to eat their candies.