Elementary School Lessons

Useful Materials from the Earth

The Earth is a rich source of useful materials:

1. water
2. food
3. oxygen
4. materials for shelter
5. materials for clothing
6. crude oil

Atmosphere

Air is a mixture of gases. Some of the gases are needed by living things to survive. The layers of air that cover the Earth is called atmosphere.

Weather

Weather is the condition of the atmosphere on a given time and place. Weather changes and it affects our daily activities. People should always be prepared for any changes in the weather.

Landforms

There are seven continents around the world.

1. Asia, the largest and about one-third of the total land area on Earth.
2. Africa
3. North America
4. South America
5. Antarctica
6. Europe
7. Oceania

The different landforms are:

1. Mountains, elevated landforms
2. Mountain range, a group of closely spaced mountains
3. Volcano, an opening in the Earth’s crust from which very hot flowing materials and gas erupt
4. Hill, an elevated landform smaller than a mountain
5. Plain, a vast, flat landform
6. Valley, landform between mountains
7. Island, a piece of land surrounded by water

Bodies of Water

There are five oceans in the world.

1. Pacific Ocean – the largest which occupies about one-third of the total Earth’s surface.
2. Atlantic Ocean
3. Indian Ocean
4. Southern Ocean
5. Arctic Ocean

Seas are smaller than oceans. Some examples are the China Sea and the Celebes Sea.

Lakes are small bodies of water surrounded by land.

The flowing bodies of water are streams, rivers, and waterfalls. Their water flows to the sea.

Water may be saltwater or freshwater.

Water from the sea is called saltwater and it is salty.

Water from rivers and lakes is called freshwater and it is not salty.

Maps

A map is a guide travelers use to find places. There are different kinds of maps.

1. street maps that show the streets of a city or a town
2. road maps that show roads connecting cities and towns
3. topographic maps shows not only the roads but also the height of the landforms

A globe is a model of the Earth.

Earth

Earth is the planet where we live. It is round and big. Its surface is mostly covered with water.

It takes about 24 hours or one day for the Earth to complete one spin or rotation. It takes about 365 days or one year to completely circle the sun or revolution.

Lesson 10

You Hear sounds

Sound is produced by the rapid back-and-forth movement of an object. Sound may be pleasant or unpleasant.