Standards:

4.OA.4 Find all factor pairs for a whole number in the range 1-100. Recognize that a whole number is a multiple of each of its factors. Determine whether a given whole number in the range 1-100 is a multiple of a given one-digit number. Determine whether a given whole number in the range 1-100 is prime or composite.

Objectives:

Math Objective: I can organize my thinking using a T-chart as I create lists of factors for a given number in the range of 1-100.

Language Objective: I can discuss how I know that a list of factors is complete.

Vertical Alignment:

3.OA.7 Fluently multiply and divide.

4.OA.4 Find all factor pairs for a whole number in the range 1-100. Recognize that a whole number is a multiple of each of its factors. Determine whether a given whole number in the range 1-100 is a multiple of a given one-digit number. Determine whether a given whole number in the range 1-100 is prime or composite.

Notes:

When teaching about multiples of single digit numbers, many teachers want to teach the divisibility rules. While these rules do tie into place value, number sense, and mathematical understanding, they are not included in these lessons because these rules often become a trick for solving rather than leading to real understanding. If students discover the patterns that the rules are created from, celebrate and then use the rules in the classroom. Do not, however, teach the rules explicitly. In this lesson, for example, students may discover that every even number is a multiple of 2; therefore, every even number is divisible by 2.

Lesson Outline:

🚀Launch

Students are asked to think about how multiplication or division could help them with a word problem. They do not need to solve the problem; the problem will be revisited later.

5.3 launch 1.PNG

🤔Explore

This section explains T-Charts. Doing this portion in class or recording yourself explaining/modeling is strongly suggested. The instructions, along with examples, are typed out for students to read, but an explanation by the student's teacher is preferred. (See steps 4-9) in Advantage Math. After the explanation, students will try making their own T-Chart for the number 30.

💬Discuss

Students will now try the same question from the Launch portion, using a T-Chart to help this time. They will post their answer and include if they believe there is only one right answer or many answers and how the T-Chart helped them.

✅Exit Ticket

Students will complete the question below, then reflect on their learning.

(There are more questions in Advantage Math if more practice is needed.)

5.3 exit ticket 2.PNG

Additional Resources:

Differentiation:

Challenge: For students who need a challenge, shorten the time allowed on the Fast Factor Game to 20 seconds or less.

Struggling: For students who are struggling with multiplication facts and basic division, modify the activity of this lesson by allowing them to use square tiles to model each number and systematically check for an array that is one row, two rows, three rows, etc. They may also choose to use a multiplication chart to look for factors.