Outer Space #1
Outer Space #2
Animals #1
Animals #2
Volcano #1
100

Equator

An imaginary line halfway between the North and South Pole

100

Star

A huge ball of hot gas that makes heat and light

100

Calf

A young mammal

100

Cold Blooded

Having a body temperature that changes with the surroundings
100
Lava
Hot, molten rock erupted from a volcano
200

Oxygen

An invisible gas in air and water that animals breath
200

Gas

Something that has no shape or size of its own

200

Predator

Animals that eat other animals

200

Camouflage

To blend in with your surroundings

200

Vent

An opening that allows air, gas or liquid to pass out of or into a space
300

Solar System

The sun and the group of planets that orbit it

300

Dwarf Planet

Smaller planets that live further away from the sun

300

Prey

Animals that are eaten by other animals

300

Molt

When a snake sheds its skin 

300

Erupt

Become active and explode lava, ash and gases

400

Orbit

The path an object follows around another object

400
Astronaut

Someone who trains to travel to outer space

400
Species

One type, or one kind of plant or animal

400

Scales 

Hard touch plates that protect the skin of a reptile or fish
400

Dormant

Temporarily inactive, slowed down, or in a deep sleep

500

Gravity

An invisible forces that pulls objects towards a planet

500

Reflect

To bounce back like a mirror does

500

Endangered

In danger of no longer existing

500

Fangs

Long, pointed teeth used to bite and tear

500

Active

Producing or involving action or motion