Baby Animals
Match an adult animal to the name of its baby in a free timed browser game. Foal, calf, lamb, cub, duckling and more.
NatureRock Types
Every rock falls into one of three groups, decided by how it formed. Below: the groups and the rocks that belong to each.
Choose your difficulty
Pick a level to start playing. You can switch at any time.
How to play
Read the rock, then tap the group it belongs to.
Tip: your progress and best score are saved in this browser only.
Related games
Animal Groups
Sort animals into the right group in a free timed browser game. Mammal, bird, fish, amphibian, reptile, insect.
NatureThe Water Cycle
Match water-cycle vocabulary to its meaning in a free timed browser game. Evaporation, transpiration, aquifers and more.
NatureWhat you are actually practicing
Every rock in the world belongs to one of three groups, and the group is decided entirely by how the rock formed. That single question separates igneous, sedimentary and metamorphic, and once you know the three stories the classification is nearly automatic.
The three stories are worth learning properly rather than memorising as lists. A rock that cooled from magma or lava is igneous. A rock made of layers of deposited material is sedimentary. A rock that was changed by heat and pressure inside the earth is metamorphic.
How the game works
You are shown a rock and four possible types. Tap the right one. A wrong pick shows the answer immediately.
Easy uses the seven rocks that appear in school textbooks. Medium widens the pool. Hard uses the full list, including the less common ones.
The links worth knowing
Igneous, formed from cooled magma or lava: granite, basalt, obsidian, pumice, tuff, pegmatite. Obsidian is cooled lava so fast that no crystals form at all, which is why it looks like glass. Pumice is the opposite, full of gas bubbles.
Sedimentary, formed from deposited layers: limestone, shale, sandstone, coal, chalk, conglomerate, flint. Limestone is usually made of shell fragments, and chalk is a softer limestone made of tiny marine organisms.
Metamorphic, changed by heat and pressure: marble, slate, gneiss, quartzite, soapstone, anthracite. Marble is limestone that has been cooked, and slate is shale that has been squeezed. Anthracite is coal that has been compressed into the hardest form.
How to get faster
Ask where the rock was when it formed. Cooled from a melt means igneous. Layered and often containing shells means sedimentary. Changed from another rock, and often crystalline, means metamorphic.
A note on coal
Coal appears in both lists, which is a fair question. Ordinary coal is sedimentary, formed from compressed plant material in layers. Anthracite is the extreme grade of the same material after further heat and pressure, and it is classed as metamorphic. The name is the only clue you get.