This set of lessons are appropriate for the beginning of a muliplication unit for grade 5 and up or towards the end of a multiplication lesson grade 4.
I make a point of really hamming it up about how difficult math can be and how these actors were famous for making simple things really funny. The more animated and enthusiastic the teacher is, the more engaged the studnets will be.
Explain to students how challenging math can be for everyone and how these two actors made fun of how complicated math can be. Show the Abbot and Costello video https://www.youtube.com/watch?v=XnICFjDn97o - this is the one where they are explaining how to mulitply 7x13.
Challenge students to create their own video to explain how to correctly multiply 7x13 and figure out where the mistakes were made. Decide how you would guide these gentlemen through the process.
2 Direct Instruction
Have students work out the answer to how many vacuums each salesman has to sell, what does 13x7 actually equal and how can you figure it out. Demonstrate a few strategies. Here is also where you can decide how much multiplication practice students will need.
3 Guided and Independent Practice
Have students work through the muliplication segment of this fantastic resource. Here they can practice their skills and get feedback immediately. As the teacher, you can circulate amoung students to determine how well they are doing with the concept. You can also work individually with students should they need more independent support.
4 Wrap Up
Have students explain their strategy for multiplying 2 digit numbers. For your stronger students they can find another set of numbers to act out like Abbot and Costello. They can also explain where the characters were going wrong in their thinking and how the student could show them their error.
Key Standards Supported
Operations And Algebraic Thinking
Fluently multiply and divide within 100, using strategies such as the relationship between multiplication and division (e.g., knowing that 8 × 5 = 40, one knows 40 ÷ 5 = 8) or properties of operations. By the end of Grade 3, know from memory all products of two one-digit numbers.
Interpret products of whole numbers, e.g., interpret 5 × 7 as the total number of objects in 5 groups of 7 objects each. For example, describe a context in which a total number of objects can be expressed as 5 × 7.
Interpret whole-number quotients of whole numbers, e.g., interpret 56 ÷ 8 as the number of objects in each share when 56 objects are partitioned equally into 8 shares, or as a number of shares when 56 objects are partitioned into equal shares of 8 objects each. For example, describe a context in which a number of shares or a number of groups can be expressed as 56 ÷ 8.
Use multiplication and division within 100 to solve word problems in situations involving equal groups, arrays, and measurement quantities, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem.1
Determine the unknown whole number in a multiplication or division equation relating three whole numbers. For example, determine the unknown number that makes the equation true in each of the equations 8 × ? = 48, 5 = _ ÷ 3, 6 × 6 = ?.
Solve two-step word problems using the four operations. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding.3
Identify arithmetic patterns (including patterns in the addition table or multiplication table), and explain them using properties of operations. For example, observe that 4 times a number is always even, and explain why 4 times a number can be decomposed into two equal addends.
Apply properties of operations as strategies to multiply and divide.2 Examples: If 6 × 4 = 24 is known, then 4 × 6 = 24 is also known. (Commutative property of multiplication.) 3 × 5 × 2 can be found by 3 × 5 = 15, then 15 × 2 = 30, or by 5 × 2 = 10, then 3 × 10 = 30. (Associative property of multiplication.) Knowing that 8 × 5 = 40 and 8 × 2 = 16, one can find 8 × 7 as 8 × (5 + 2) = (8 × 5) + (8 × 2) = 40 + 16 = 56. (Distributive property.)
Understand division as an unknown-factor problem. For example, find 32 ÷ 8 by finding the number that makes 32 when multiplied by 8.
Reasoning With Equations And Inequalities
Explain each step in solving a simple equation as following from the equality of numbers asserted at the previous step, starting from the assumption that the original equation has a solution. Construct a viable argument to justify a solution method.
Solve simple rational and radical equations in one variable, and give examples showing how extraneous solutions may arise.