Lesson 2: What Is Multiplication?

Getting Started

Questions to Explore

  • What is multiplication?
  • Why do we multiply?
  • How do we read and write in mathematical language?

Facts and Definitions

  • Multiplication: mathematical operation that requires adding a number to itself a certain number of times; repeated addition
  • Factor: number that is multiplied
  • Product: the answer to a multiplication problem
  • ×: mathematical symbol that means we multiply; also called the times symbol or times sign

Skills

  • Interpret products of whole numbers (for example, interpret 5 × 7 as the total number of objects in 5 groups of 7 objects each)
  • Use the language of multiplication

Materials

  • "Equal Groups" sheet from Lesson 1
  • colored pencils
  • construction paper (kit)
  • counters (kit)
  • fine point dry-erase markers (kit)
  • glue or glue stick
  • Interactive Notebook
  • scissors
  • whiteboard (kit)

Introduction

Materials: "Equal Groups" sheet from Lesson 1
Ask your child to look at the "Equal Groups" sheet that she put in her Interactive Notebook during the previous lesson. Depending on the things that she listed, pose questions that ask her to find sums based on the number of items in specific groups. For example, you might ask, "How many legs do five horses have?" (20) and "How many sides do two stop signs have?" (16) Allow your child to use the whiteboard and a dry-erase marker to draw or write to find the answers to your questions, and pose four or five different questions using different things from her lists.

Now, say, "Skip counting, arrays, and repeated addition can help you find sums when you're adding more than two things together, but there's another mathematical operation that's much quicker than addition — it's called multiplication. You're going to start learning about that today."