Science (EVS K-5) · Class 3 · Things We Make and Do · Term 3

Building with Bricks and Cement

Understand the materials like bricks, cement, and sand that are used to build strong houses.

TL;DR:Let's put on our builder hats and investigate the secrets behind strong houses. What magical ingredients do we mix together to build walls that can stand tall for years?

• CBSE Learning Outcomes
• NCERT EVS Class 3: Theme - Things We Make and Do

About This Topic

This topic, 'Building with Bricks and Cement', is a fundamental part of the Environmental Studies (EVS) curriculum for Class 3, aligning with the NCF's emphasis on connecting classroom learning to the immediate environment. It transitions students from simply identifying different types of houses (kutcha and pucca) to understanding the 'why' behind their construction. The focus is on materials science at a very basic level, encouraging observation, comparison, and inquiry into the properties of common building materials.

By exploring bricks, cement, and sand, students learn about man-made materials and how they are processed and combined to create strong, durable structures. This topic provides an excellent opportunity to introduce concepts of material properties (hardness, strength), processes (mixing, baking), and the importance of shelter for safety and well-being. It serves as a foundational block for later concepts in physics and chemistry, while remaining grounded in the tangible, everyday context of the homes and buildings students see around them.

Key Questions

1. Explain why cement is mixed with sand and water to build walls.
2. Compare a brick wall with a mud wall.
3. Identify the main material used to make a brick.

Learning Objectives

• Identify the key materials used to build a pucca house: bricks, cement, sand, and water.
• Describe the function of mortar (cement, sand, and water mixture) as a binding agent.
• Explain that bricks are made from clay and are hardened by baking in a kiln.
• Compare the strength and durability of a brick wall with a mud wall.
• Recognise the importance of using strong materials for building safe and long-lasting houses.

Key Vocabulary

Brick	A rectangular block made of baked clay, used for building walls.
Cement	A fine grey powder that, when mixed with water and sand, hardens and acts like a glue for bricks.
Mortar	The thick paste made by mixing cement, sand, and water, used to join bricks.
Kiln	A very hot, large oven used for baking clay to turn it into hard bricks. In Hindi, it is called a 'bhatta'.
Foundation	The strong base built underground on which the entire house rests.

Watch Out for These Misconceptions

Common Misconception

Cement is a type of super glue that works by itself.

What to Teach Instead

Cement is a special powder that needs to be mixed with sand and water to work properly. This mixture, called mortar, undergoes a chemical reaction that makes it hard like a rock, binding the bricks together firmly.

Common Misconception

Bricks are just rectangular blocks of dried mud.

What to Teach Instead

While bricks start with a special type of clay soil, they are not simply left to dry in the sun. They are baked at very high temperatures in a special oven called a kiln, which makes them very hard, strong, and water-resistant.

Common Misconception

You can build a wall with just cement and water.

What to Teach Instead

A mixture of only cement and water would be very brittle and crack easily. Sand is added to make the mortar strong, prevent shrinkage cracks, and also make it more economical.

Active Learning Ideas

Stations Rotation

Mini Mortar Makers

Students work in small groups to mix sand, flour (as a safe cement substitute), and water to create a paste. They then use this 'mortar' to stick together small pebbles or toy blocks, observing how it hardens and binds the items.

25 min·Small Groups

Stations Rotation

The Strength Test: Brick vs. Mud

In pairs, students build two small, model walls: one with clay or mud, and another with toy bricks (like LEGOs or wooden blocks). They can then gently push on both or spray a little water to compare their strength and durability.

30 min·Pairs

Stations Rotation

Construction Site I-Spy

Take the class on a supervised walk around the school premises or show them pictures/videos of a construction site. Students have to spot and name the different materials they see being used, such as bricks, cement bags, sand piles, and steel rods.

20 min·Whole Class

Real-World Connections

• Observing local masons (raj mistri) at work and seeing how they mix mortar and lay bricks.
• Identifying different buildings in their locality, like their school, hospitals, and shops, and noting that they are mostly made of brick and cement.
• Understanding why pucca houses are essential for safety during monsoons and storms in many parts of India.
• Discussing the different types of houses seen in Indian villages and cities, from mud huts to multi-storey apartments.
• Connecting the topic to professions like architects, civil engineers, and construction workers.

Assessment Ideas

Quick Check

Give students a picture of a house being built and ask them to circle and label the different materials like bricks, cement mixture, and sand.

Quick Check

A short quiz with fill-in-the-blanks and true/false questions, such as '______ is mixed with sand and water to join bricks.' or 'Mud walls are stronger than brick walls (True/False)'.

Quick Check

Students complete a 'K-W-L' chart (What I Know, What I Want to Know, What I Learned) about building materials before and after the lesson.

Frequently Asked Questions

Why are most bricks red in colour?

The red colour of bricks comes from the iron present in the clay used to make them. When the bricks are baked at high temperatures in a kiln, the iron reacts with oxygen and turns red, similar to how iron rusts.

Can we build a house underwater using cement?

Yes, special types of cement, called hydraulic cement, can harden even underwater. This is used to build bridges, dams, and foundations in wet areas.

What is the difference between cement and concrete?

Cement is just one ingredient, a powder. When you mix cement, sand, water, and small stones (gravel), you get a very strong material called concrete, which is used to make pillars, roofs, and roads.