4

Extreme Earth

4

Earthquakes

3

Amazing Earth - Part 2

3

The Earth

3

Amazing Earth - Part 1

3

Stars

4

Volcanoes

4

Aquatic

4

Extreme Weather

3

Straits of the World

4

Polar

2

Four Seasons! Deciduous Forest

2

Landforms

4

Belém Tower, Portugal

3

Senses

2

Treeless Plains! Steppe

4

Ecosystems Level 4

3

Drainage Basins of the World

3

Gravity

3

Saturn

3

Caves of the World

4

The Golden Gate Bridge

3

Pressure

3

Trenches of the World

1

Animals and their homes

3

Mars

2

Solar System

4

Montane Forest

3

Space Exploration

3

Continents of the World