Science for Grade 2
1 Introduction to Science
1-1 What is Science?
1-2 Importance of Science in Everyday Life
1-3 Basic Scientific Tools and Equipment
2 The Living World
2-1 Living and Non-Living Things
2-2 Characteristics of Living Things
2-3 Plants
2-3 1 Parts of a Plant
2-3 2 Functions of Plant Parts
2-3 3 Types of Plants
2-4 Animals
2-4 1 Types of Animals
2-4 2 Characteristics of Different Animals
2-4 3 Animal Habitats
3 The Human Body
3-1 Parts of the Human Body
3-2 Functions of Body Parts
3-3 Basic Needs of Humans
3-4 Health and Hygiene
4 The Earth and Beyond
4-1 The Earth
4-1 1 Earth’s Surface
4-1 2 Land and Water Forms
4-2 The Sky
4-2 1 Sun, Moon, and Stars
4-2 2 Day and Night
4-2 3 Weather and Seasons
5 Materials and Their Properties
5-1 Types of Materials
5-2 Properties of Materials
5-3 Changes in Materials
5-4 Recycling and Conservation
6 Forces and Motion
6-1 What is a Force?
6-2 Types of Forces
6-3 Motion
6-4 Simple Machines
7 Energy and Its Forms
7-1 What is Energy?
7-2 Types of Energy
7-3 Sources of Energy
7-4 Energy Conversion
8 Simple Experiments and Observations
8-1 Importance of Experiments
8-2 Basic Scientific Method
8-3 Simple Experiments to Observe Scientific Concepts
9 Safety in Science
9-1 Importance of Safety
9-2 Safety Rules in the Science Lab
9-3 Handling Equipment and Materials Safely
The Earth

The Earth

1. The Earth's Structure

The Earth is made up of several layers. The outermost layer is the crust, which is where we live. Below the crust is the mantle, a thick layer of hot, semi-solid rock. The core is at the center of the Earth and is made up of a solid inner core and a liquid outer core. The core is very hot, almost as hot as the surface of the Sun.

Imagine the Earth as a big, layered cake. The crust is like the icing on top, the mantle is like the cake layers, and the core is like the filling in the middle. Each layer has its own special job to keep the Earth working properly.

2. The Earth's Atmosphere

The atmosphere is the layer of air that surrounds the Earth. It is made up of different gases, mainly nitrogen and oxygen. The atmosphere protects us from harmful rays from the Sun, keeps the Earth warm, and provides the air we breathe. The atmosphere is divided into several layers, with the troposphere being the closest to the Earth and where weather happens.

Think of the atmosphere as a blanket that covers the Earth. Just like a blanket keeps you warm at night, the atmosphere keeps the Earth warm and protects it from the cold space outside.

3. The Earth's Water Cycle

The water cycle is the continuous movement of water on, above, and below the surface of the Earth. It involves processes like evaporation, condensation, and precipitation. Water from oceans, rivers, and lakes evaporates into the air, forms clouds, and then falls back to the Earth as rain or snow. This cycle is important for providing fresh water and supporting life on Earth.

Imagine the water cycle as a big, never-ending loop. Water goes up into the sky like a hot air balloon, turns into clouds, and then comes back down as rain to start the cycle all over again.

4. The Earth's Rotation and Revolution

The Earth rotates on its axis, which is an imaginary line that runs through the North and South Poles. This rotation causes day and night. The Earth also revolves around the Sun, which takes about 365 days, or one year. This revolution causes the changing of seasons as the Earth tilts on its axis.

Think of the Earth as a spinning top that also moves around a big, bright light (the Sun). The spinning top makes day and night, and the movement around the light makes the seasons change.