# how to make working model for teaching mensuration formulas

Creating a working model for teaching mensuration formulas can be a highly effective Teaching Learning Material (TLM). Here are some ideas and instructions on how to make a comprehensive, interactive model that helps students understand and apply various mensuration formulas:

### Materials Needed

• Cardboard
• Scissors
• Glue
• Markers
• Ruler
• Protractor
• String
• Compass
• Transparent plastic sheet (optional)
• Small whiteboard or cardboard for writing formulas
• Colored paper or felt

### Step-by-Step Video Instructions

#### 2D Shapes Model

1. Square:
• Cut out a square from cardboard.
• Write the formulas for the area (A = side²) and perimeter (P = 4 × side) on a small piece of paper or cardboard.
• Attach the formulas to the square.
2. Rectangle:
• Cut out a rectangle from cardboard.
• Write the formulas for the area (A = length × breadth) and perimeter (P = 2 × (length + breadth)).
3. Triangle:
• Cut out a triangle from cardboard.
• Write the formulas for the area (A = ½ × base × height) and perimeter (P = a + b + c), and Heron’s formula (A = √[s(s-a)(s-b)(s-c)], where s = (a+b+c)/2).
4. Circle:
• Cut out a circle from cardboard using a compass.
• Write the formulas for the area (A = πr²) and circumference (C = 2πr).

#### 3D Shapes Model

1. Cube:
• Construct a cube using cardboard.
• Write the formulas for the surface area (SA = 6a²) and volume (V = a³).
2. Cuboid:
• Construct a cuboid using cardboard.
• Write the formulas for the surface area (SA = 2(lb + bh + hl)) and volume (V = lbh).
3. Cylinder:
• Construct a cylinder using cardboard for the curved surface and circles for the bases.
• Write the formulas for the surface area (SA = 2πr(h + r)) and volume (V = πr²h).
4. Cone:
• Construct a cone using cardboard for the curved surface and a circle for the base.
• Write the formulas for the surface area (SA = πr(r + l), where l is the slant height) and volume (V = ⅓πr²h).
5. Sphere:
• Use a Styrofoam ball or construct a sphere from cardboard.
• Write the formulas for the surface area (SA = 4πr²) and volume (V = ⅘πr³).
6. Pyramid:
• Construct a pyramid using cardboard.
• Write the formulas for the surface area (SA = B + ½Pl, where B is the base area, P is the perimeter of the base, and l is the slant height) and volume (V = ⅓Bh, where B is the base area and h is the height).

### Assembly and Presentation

1. Base Board: Use a large cardboard sheet as the base.
• Attach each shape with its corresponding formulas on the base board.
• Arrange 2D shapes on one side and 3D shapes on the other for better organization.
2. Interactive Elements:
• Use Velcro or magnets to make shapes detachable so students can handle and explore them.
• Add flaps or sliders to cover and reveal formulas for an interactive quiz feature.
3. Formula Display:
• Use a small whiteboard or a piece of cardboard to write and explain the formulas.
• Attach this to the base board for easy reference.
4. Color Coding:
• Use different colors for different shapes to make the model visually appealing and easier to understand.
• Color-code the formulas to match the shapes.

By creating these interactive and visually engaging models, you can make learning mensuration concepts more accessible and enjoyable for students.