Ocean Life

27 Skills in Science. 21 are ready to try — three verified questions each, no account needed.

Ready to try

Ages 5–7
Coasts & Beaches
Know what a coast or beach is — the place where land meets the ocean — and that different coasts can be sandy, rocky, or muddy, each with different plants and animals
9 verified questions on this shelf
Ages 5–7
Ocean Food Chains
Describe a simple ocean food chain: tiny plants (phytoplankton) are eaten by small animals, which are eaten by bigger fish, which are eaten by top predators like sharks — showing that all ocean life depends on others for food
9 verified questions on this shelf
Ages 5–7
Whales & Dolphins Are Mammals
Know that whales and dolphins are mammals, not fish — they breathe air, are warm-blooded, and feed their babies milk — even though they live in the ocean
9 verified questions on this shelf
Ages 5–7
What Is the Ocean?
Know that oceans are huge bodies of salt water that cover most of Earth's surface, and that the ocean is home to an enormous number of living things
9 verified questions on this shelf
Ages 5–7
What Ocean Animals Need
Understand that ocean animals need food, shelter, and the right conditions to survive — just like land animals — and that different parts of the ocean provide for different animals' needs
9 verified questions on this shelf
Ages 7–9
Classifying Ocean Animals
Classify ocean animals into major groups: fish (breathe through gills, have scales), marine mammals (breathe air, warm-blooded, feed milk), and invertebrates (no backbone — jellyfish, octopuses, crabs, starfish)
9 verified questions on this shelf
Ages 7–9
Coral Reefs
Know that coral reefs are built by tiny living animals called coral polyps, that reefs are home to more species than almost any other ocean habitat, and that they are sometimes called the 'rainforests of the sea'
9 verified questions on this shelf
Ages 7–9
Ocean Animal Adaptations
Understand that ocean animals have special adaptations for their environment: streamlined bodies for fast swimming, camouflage to hide from predators, blubber to keep warm in cold seas, and tentacles or suckers to catch prey
9 verified questions on this shelf
Ages 7–9
Ocean Food Webs
Understand ocean food webs: multiple interconnected food chains where energy flows from phytoplankton (producers) through zooplankton, small fish, and large predators, and that removing one species affects the whole web
9 verified questions on this shelf
Ages 7–9
The Five Oceans
Name and locate the five oceans — Pacific (largest), Atlantic, Indian, Southern, and Arctic (smallest and coldest) — on a world map, and understand that they are all connected as one global ocean
5 verified questions on this shelf
Ages 7–9
Tides, Waves & Currents
Know that the ocean has tides (water level rises and falls twice a day, caused mainly by the Moon's gravity), waves (caused by wind), and currents (rivers of water flowing through the ocean that carry warmth and nutrients around the world)
9 verified questions on this shelf
Ages 9–11
Deep-Sea Creatures
Explore life in the deep sea: animals that make their own light (bioluminescence), creatures adapted to crushing pressure and total darkness, and hydrothermal vents where life thrives without sunlight
9 verified questions on this shelf
Ages 9–11
Exploring the Ocean
Know that oceanographers and marine biologists study the ocean using submarines, remotely operated vehicles (ROVs), satellites, and diving, and that much of the ocean remains unexplored — we know more about the Moon's surface than the deep…
9 verified questions on this shelf
Ages 9–11
Ocean Pollution & Harm
Identify ways humans harm the ocean — plastic pollution, overfishing, oil spills, and ocean acidification from carbon dioxide — and understand that most ocean pollution comes from land-based activities, not just ships
9 verified questions on this shelf
Ages 9–11
Oceans & Climate
Understand the connection between the ocean and climate: the ocean absorbs heat and carbon dioxide, drives weather patterns through evaporation, and ocean currents distribute warmth around the planet — making the ocean Earth's climate engi…
9 verified questions on this shelf
Ages 9–11
Protecting the Ocean
Understand how people protect the ocean: marine protected areas limit fishing and pollution, sustainable fishing prevents overharvesting, beach clean-ups reduce plastic, and international agreements aim to reduce carbon emissions that caus…
9 verified questions on this shelf
Ages 11–13
Deep-Sea Life Without Sunlight
Contrast photosynthesis (energy from sunlight) with chemosynthesis (energy from oxidising chemicals like hydrogen sulphide); describe hydrothermal vent communities: chemoautotrophic bacteria form the base of a food web supporting tube worm…
5 verified questions on this shelf
Ages 11–12
Ocean Currents and Global Heat
Explain thermohaline circulation (the global conveyor belt) as driven by temperature and salinity differences that cause dense water to sink; describe how the Atlantic Meridional Overturning Circulation (AMOC) transfers heat from the tropi…
9 verified questions on this shelf
Ages 12–13
Coral Bleaching & Acidification
Explain the mutualistic symbiosis between coral polyps and photosynthetic zooxanthellae; describe how heat stress causes bleaching (corals expel zooxanthellae and turn white); explain ocean acidification chemistry: CO2 dissolves in seawate…
9 verified questions on this shelf
Ages 12–14
Predator Loss and Ecosystem Effects
Quantify energy transfer efficiency through trophic levels (~10% rule); explain trophic cascades: how removing an apex predator triggers a chain of ecosystem changes (sea otters → sea urchin explosion → kelp forest collapse); define 'fishi…
6 verified questions on this shelf
Ages 13–14
Deep-Ocean Exploration Technology
Explain how crewed submersibles (Alvin, Deepsea Challenger) and remotely operated vehicles (ROVs) allow exploration of the deep; describe acoustic seafloor mapping using sonar and why only ~25% of the ocean floor has been mapped at high re…
9 verified questions on this shelf

Being planted

These Skills are on the map, but their questions are still being written and checked.

Ages 5–7
Ocean Animal Variety
Coming soon
Ages 5–7
Rock Pool Habitats
Coming soon
Ages 7–9
Ocean Depth Zones
Coming soon
Ages 7–9
The Ocean Floor
Coming soon
Ages 9–11
Ocean Animal Migrations
Coming soon
Ages 9–11
Ocean Ecosystems
Coming soon

Skill names and descriptions include the Marble Skill Taxonomy © Generative Spark, Inc. (withmarble.com), licensed under ODbL 1.0 (database) and CC BY-SA 4.0 (content). Practice questions are GlowGrades's own, each checked by independent verifiers that must agree before a child ever sees it.