Lesson 2

Measuring Area

Est. Class Sessions: 1–2
X

Mathematical Standards

3.MD.C
Geometric measurement: understand concepts of area and relate area to multiplication and to addition. (3.MD.C.5, 3.MD.C.6)

Standards for Mathematical Practice

MP1.
Make sense of problems and persevere in solving them.
MP2.
Reason quantitatively.
MP3.
Construct viable arguments and critique the reasoning of others.
MP4.
Model with mathematics.
MP5.
Use appropriate tools strategically.
MP6.
Attend to precision.

Professor Peabody is covering his living room and hall with square tiles. Students help him determine how many tiles he will need. Students expand their understanding of area by measuring the area of irregular shapes. They count whole square units and piece together the remaining fractional pieces to make whole tiles.

Content in this Lesson

  • Understanding that area is the amount of surface to be covered [E1, E3].
  • Recognizing that the area stays the same though different units of measure are used.
  • Measuring area by counting whole and fractional parts of square centimeters [E3].
  • Finding the area of shapes with curved and straight sides [E3].

Daily Practice and Problems E–F

E. Large Orders

F. What Time Is It?

X

Materials for Students

Daily Practice and Problems Lesson Homework Assessment

Student Books

 Student Guide    
Student Activity Book    

Teacher Resources

 Teacher Guide - digital    

Materials for the Teacher

Display of Centimeter Grid Paper Master (Teacher Guide)
Display of the Measuring Area pages (Student Guide) Pages 99–100
Display of Check Each Other page (Student Activity Book) Page 147
Unit 5 Assessment Record
display set of square-inch tiles
clear plastic ruler
scissors, optional
envelopes, optional

Materials Preparation

Draw a Polygon on a Display of the Centimeter Grid Paper Master. The polygon should be irregular and should include partial square centimeters to demonstrate how these can be put together. See Figure 1 for an example. Draw and label a square centimeter as shown.

Prepare the Putting Pieces Together Masters for a Learning Center. Make enough copies of the Putting Pieces Together pages for the number of students visiting the center at one time. Follow the directions on the second page to cut apart the pieces. Place each set of pieces in an envelope or container. Students should not see the shapes together prior to the activity.

Prepare the Make Your Own Shape Masters for a Learning Center. Make enough copies of the first page of the Make Your Own Shape Masters for the number of students visiting the center at one time. Pages can be cut in half to yield 2 sheets of directions. Make enough copies to cut the grid pages in half so each student has one small grid to work with in the learning center. Make a few extras in case of mistakes.

Assessment in this Lesson

Assessment Expectation Assessed

Measuring Area
Check-In: Questions 1–6
Student Guide
Pages 99–100
E3.
Find the area of shapes with straight or curved sides by counting square units.