To set the stage for this lesson, you may wish to read one of the books listed in the
Bibliography of Books About Multiplication,
What Comes in 2's, 3's, and 4's.
You may also wish to discuss some examples from science such as:
- If a starfish has 5 arms, how many arms will 2 starfish have?
- If a spider has 8 legs, how many legs will 4 spiders have?
This is also a good time to relate multiplication to addition, in that multiplication is repeated addition. In the example, "If a starfish has 5 arms, how many arms will 2 starfish have?", students may recognize the mulitplication fact 5 × 2 = 10, and they may recognize the addition fact 5 + 5 = 10.
Provide students with counters, pieces of string or yarn, and a workmat (large construction paper). Tell them that they will be making equal sets and finding out how many counters there are in all. Ask them to make 5 sets of 4 counters, with each set inside
its own yarn circle. Then tell them to determine in any way they wish how many counters they have used. Next display an empty table with several rows in which the three columns are labeled "Number of Sets, Number in Each Set, and Number in All". Have them suggest what will go in each column (5, 4, 20). Then have them work in pairs to create new equal set models for addition. When they have identified the product, help them enter their findings on their Equal Sets activity sheet.
You may wish to review the terms factor, multiple, and product.
Allow the children time to make several entries, then ask them if they see any similarities among the entries. If examples of the order property are not mentioned, prompt them to notice such entries. Encourage students to also notice rows in which the last column shows the same number.
To provide an application for this model, have the children create pictographs of favorite fruit. If the children are not familiar with pictographs in which an icon stands for multiple data points, you might demonstrate one or find an example in their Social Studies textbook. Ask the students to vote for their favorite fruit, limiting the choices to a set number of possible selections. Then ask them to tally the collected data. Now assign them to groups and have each group construct a pictograph. Before they begin, you may wish to help the groups find an appropriate number for each icon to represent and also to
decide what to do if the number choosing that fruit is not a multiple of the number they chose.
When the children are ready, call them together to share the pictographs and describe how each of the entries on it was constructed.
