Grade 3

FInding the Area and the Perimeter

Computational Thinker


Area Builder is an interactive website that allows students to build shapes to find the area and the perimeter. There are two-parts for students to use, the explore and the game. The first allows for exploration while building, the second is a game that has them figuring out the area and the perimeter. There are six levels.

Students will:

  • Be able to build shapes that represent the area.
  • Understand that area is the measurement of the surface and perimeter is the measurement around the object.

Vocabulary Words:

  • Area: An area is measurement of a surface. 
  • Perimeter: The perimeter is the outermost parts or boundary of an area or object.

To prepare for this lesson:

  • Students should have been introduced to the vocabulary in the activity.
  • Students should have been introduced to area and perimeter prior to beginning Area Builder.
  • Preview the website Area Builder
  • Watch the video from Khan Academy on perimeter and area. 

See Accommodations Page and Charts on the site in the Teacher Resources. 

Directions for this activity:

  1. Introduce the students to perimeter and area with the video from Khan Academy
  2. Have the students log onto the website Area Builder.
  3. To EXPLORE click on the explore tab.
  4. Build shapes using the squares in the purple bucket. Drag them onto the graph board.
  5. Toggle the button on the right to build two different shapes to compare the area and the perimeter.
  6. The color of the square units can be changed by selecting the color preference.
  7. To play a GAME click on the game tab and select the level. The higher you go, the more challenging it will be.
  8. Check to have a grid or to leave blank.
  9. Build the area given.
  10. Check.

Different options for assessing the students:

  • Observations
  • Check for understanding
  • Share with manipulatives on the document camera.
  • Have math talks with your students.
  • Create exit tickets.
  • Have a class discussion.
  • Have the students do student presentations

MITECS: Michigan adopted the "ISTE Standards for Students" called MITECS (Michigan Integrated Technology Competencies for Students) in 2018.

Computational Thinking
5a. Students formulate problem definitions suited for technology-assisted methods such as data analysis, abstract models and algorithmic thinking in exploring and finding solutions.
5b. Students collect data or identify relevant data sets, use digital tools to analyze them, and represent data in various ways to facilitate problem-solving and decision-making.
5c. Students break problems into component parts, extract key information, and develop descriptive models to understand complex systems or facilitate problem-solving.
5d. Students understand how automation works and use algorithmic thinking to develop a sequence of steps to create and test automated solutions.

Device: PC, Chromebook, Mac, iPad

Browser: Chrome, Safari, Firefox, Edge, ALL

Apps. Extensions, Add-ons

Area Builder

Khan Academy Video


Write a set of directions on how to find area and perimeter.

Students cut out squares and build posters that explain area and perimeter.

  • Students create their own area and perimeter problems to solve with each other.
  • Area and Perimeter people activity: students build a character using grid paper and then tell the area and perimeter of each body part.

This task card was created by Julie Hoehing, Lake Shore Public Schools, February 2020. Updated December 2021.