Rectangle Maker: Make Rectangles (Random or draw your own) and Measure the Area and Perimeter | Instructions: | Suggested Lessons or Activities: | Special Features: | Other Related Modules and Useful Links:

Rectangle Maker: Make Rectangles (Random or draw your own) and Measure the Area and Perimeter

© R. Mirshahi


  • Click the rectangle maker button with the arrow pointing to it to make a new rectangle at random. You will see the rectangle's measurements close to its sides and at the top of the page you will find the area of the rectangle. You can hide the area and perimeter by clicking the "eye" and click the ruler button to measure the sides to calculate the area and perimeter. Click the "eye" again to reveal the area and perimeter and check your answers (test yourself). You can also estimate before you measure and see how close you are. The measurements are rounded to the nearest cm.

Suggested Lessons or Activities:

  • This is a good resource for estimating and measuring area and perimeter.
  • Explore how you can multiply the sides of a rectangle to find its area (A = l x w, or Area = length x width). and follow this formula to find the perimeter: P = (l +w) x 2
  • Show how a thin but long rectangle can have a small area but a large perimeter
  • Explore the concept of rounding to the nearest cm.
  • challenge students by asking them to draw a specific rectangle. For example: Draw a rectangle with the area of 24 squared cm and perimeter of 22 cm. Answer: an 8 x 3 rectangle

Also challenge students by asking question like the one below. Students will calculate the area of the bigger rectangle and subtract the area of the the smaller rectangle inside it. For students to understand this concept, use construction paper to model this problem.

As you click the reset button, the Main Activities Resource is loaded here. If you are looking for details and specific instructions and lesson ideas about the other activities, you need to go to the pages where these resources are housed.
  1. Angle Maker
  2. Line Maker
  3. Triangle Maker
  4. Draw and Measure Lines and Angles
  5. Linear Measurement Test 20 Questions

Special Features:

  • random rectangle maker (blue rectangle)
  • ability to draw your own rectangle (green rectangle)
  • automatic measurements of rectangles' sides, areas and perimeters
  • ability to hide area and perimeter
  • ability to annotate as well as draw rectangles manually
  • fully functional ruler (move, turn, click the ruler button to show or hide ruler)
  • works really well with interactive whiteboards and Flash enabled tablets
  • full screen

Other Related Modules and Useful Links: