The Earth

From space the Earth looks blue, white and brown. There are 4 parts

• the atmosphere is the air that surrounds the Earth.

Air is mainly nitrogen and oxigen. There are also small quantities of carbon dioxide, ozone and water vapour.

The atmosphere has got layers:      

Exosphere - The last layer and   the thinnest.  Thermosphere - The thermosphere is next and   the air is very thin here. Temperatures can get extremely hot in the thermosphere. Mesosphere - This is where most meteors burn up upon entry. The coldest place on Earth is at the top of the mesosphere. Stratosphere - it gets warmer the further away you get from the Earth. There is a thin layer of ozone in the upper stratosphere, This is called the  ozone layer. Troposphere - The troposphere is the layer next to the ground or surface of the Earth. This is where we live and even where planes fly.

• the hydrosphere is the water on Earth (oceans, lakes, rivers, ice and snow in the poles and mountains)

The water cycle

It is the constant circulation of water between the sea, the atmosphere and land.

1. Water evaporates because of heat from the Sun. It becomes water vapour.
2. Water vapour rises and condenses into drops of water. The water drops form clouds.
3. Water falls from clouds as rain: precipitation. When it is very cold, water solidifies and falls as snow.
4. Water flows over the land and filters into it. It forms rivers and lakes.
5. The water returns to the sea or evaporates. The water cycle starts again.

Click here to learn more things about THE WATER CYCLE.

• the biosphere is all the living things on Earth.

• the geosphere or lithosphere is the ball of rock. It has 3 layers

• The crust is made up of solid materials: rocks. Rocks are made up of minerals.

• The mantle is very hot. In some parts there is magma.

• The core is extremely hot.

ACTIVITIES

Water and air activities

Earth system cards

SONGS

Water cycle rap

PLANET EARTH

The universe has millions of galaxies. 
The Milky Way is a galaxy.






 In this galaxy we can find a giant star called  the Sun.

The Sun gives light and heat to the planets and satellites.




There are 8 planets.


Satellites orbit certain planets. The Moon is the Earth's satellite



The solar system consists of  the Sun and the celestial bodies that orbit it. Earth is a planet in the solar system

WHAT IS THE EARTH LIKE?

From space the Earth looks blue, white and brown. There are 4 parts:

• the atmosphere is the air that surrounds the Earth.

• the hydrosphere is the water on Earth (oceans, lakes, rivers, ice and snow in the poles and mountains)

• the biosphere is all the living things on Earth.

• the geosphere is the ball of rock. It has 3 layers

Game: Planet pursuit

NASA for kids

THE EARTH AND THE MOON

The Earth rotates. It takes our planet 24 hours to spin around once. This is called a day.

We have days and nights because of the rotation of the Earth.

It takes the Moon 29,5 days to go around the Earth.

The phases of the moon are the changing shapes of the bright part of the Moon that we see in the sky.

The phases of the moon

THE SEASONS

It takes the Earth a year (365 days and six hours) to revolve around the Sun. This path is called its orbit.

The seasons result from the Earth's axis being tilted to its orbital plane; it deviates by an angle of approximately 23.5 degrees. Thus, at any given time during summer or winter, one part of the planet is more directly exposed to the rays of the Sun. This exposure alternates as the Earth revolves in its orbit. Therefore, at any given time, regardless of season, the northern and southern hemispheres experience opposite seasons.

There are 4 seasons: spring, summer, autumn and winter.

The Earth, the Sun and the Moon

PLANTS

Activity 1: Growing plants

Activity 2: Helping plants grow well

Activity 3: Life cycles

MATTER

What is matter?

Matter is everything we can see, smell or touch. Air, rocks and wood are all matter

Matter makes up all the objects that surround us.

All matter has properties: mass, volume and density



                                                MASS                                         VOLUME

Density is mass per volume. To calculate density, we divide the mass of an object or a subtance by its volume.

TYPES OF MATTER

Objects can be made of different types of matter

CHANGES IN MATTER

There are 2 types of change in matter:

1. Physical changes: the object or subtances change, but the matter remains the same. When water freezes, it is still water.

• Movement: the object changes position.
• Expansion: the temperature increases and the object gets bigger. (mercury in a thermometer)
• Contraction: the temperature decreases and the object gets smaller. (If a balloon is put in a fridge the air contracts and the balloon gets smaller)
• Changes of states: when the temperature rises, the states changes. (If water is heated, it changes into steam.)
• Fragmentation: the object is divided into small pieces. (If a glass breaks, the pieces are still made of glass.)

2. Chemical changes.

• Oxidation: One subtance changes into another when it reacts with oxigen. (Iron changes into rust)
• Combustion: When an object or subtance is burried, it changes into another substance. (when wood burns, it changes into ashes and gases)
• Putrefaction: This occurs when a living thing decomposes. (when an apple decays, its appearance, colour, smell and taste changes)

States of matter

Matter has 3 states:

Solids have their own shape.

Liquids don't have their own specific shape. They have the shape of the container which holds them.

Gases don't have a specific shape. They expand.

Matter can change from one state to another when temperature changes.

• Melting: a solid changes into a liquid.
• Solidification: a liquid changes into a solid.
• Boiling: a liquid changes into a gas.
• Evaporation: a liquid changes into a gas.
• Condensation: a gas changes into a liquid.
• Sublimation: a solid changes into a gas.

Matter can be classified into:

           mixtures    and      pure subtances

Pure subtances are made up of one single component.

Mixtures are made up of different component. In some mixtures we can distinguish the components.

Activities

Activity 1: Changing states

Activity 2: Gases around us

Activity 3: Solids and liquids

States of Matter millionaire game