Estimate Products

10 min

Narrative

The purpose of this Warm-up is for students to reason about the side lengths of a garden with a given area in preparation for an upcoming activity. If students do not name any fractional side lengths, ask the Activity Synthesis question to prompt that discussion.

Launch

  • Groups of 2
  • Display the image.
  • “What do you notice? What do you wonder?”
  • 1 minute: quiet think time
Teacher Instructions
  • “Discuss your thinking with your partner.”
  • 1 minute: partner discussion
  • Share and record responses. 
  • “If the garden is between 30 square feet and 40 square feet, what are some possible side lengths?” (8 feet by 4 feet, 7 feet by 5 feet)
  • Share and record responses.

Student Task

What do you notice? What do you wonder?

image of garden,<span> has 3 sections,</span><span> bushes and poles next to garden.</span>

Sample Response

Students may notice:

  • There are 3 sections in the garden. 
  • There are bushes next to the garden.

Students may wonder:

  • What are the poles that are standing up?
  • What is the area of the garden?
  • What is growing in the garden?
Activity Synthesis (Teacher Notes)

  • “Would side lengths of 10 feet and 3183 \frac{1}{8} feet be possible based on the area?” (Yes, because 10 times 3 is 30 and 10×1810 \times \frac{1}{8} is more than 1 but less than 2. So, the area would be more than 30 but less than 40.)

Standards
Building Toward
  • 5.NF.4·Apply and extend previous understandings of multiplication to multiply a fraction or whole number by a fraction.
  • 5.NF.B.4·Apply and extend previous understandings of multiplication to multiply a fraction or whole number by a fraction.

20 min

15 min