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weathering
Article
EDUCATION

weathering

Weathering describes the breaking down or dissolving of rocks and minerals on the surface of the Earth. Water, ice, acids, salts, plants, animals, and changes in temperature are all agents of weathering.

  • Best for: Grades 6+ (ages 11+)
  • Concepts: erosion, geology, landscape, rocks, weathering
erosion
Article
EDUCATION

erosion

Erosion is the geological process in which earthen materials are worn away and transported by natural forces such as wind or water.

  • Best for: Grades 6+ (ages 11+)
  • Concepts: erosion, geology, ice, landforms, landscape, physical geography, sediment, water, wind
civilization
Article
EDUCATION

civilization

Civilization describes a complex way of life characterized by urban areas, shared methods of communication, administrative infrastructure, and division of labor.

  • Best for: Grades 5+ (ages 10+)
  • Concepts: architecture, civilizations, class, communication, conflict, culture, exploration, human geography, infrastructure, trade, urban areas
climate
Article
EDUCATION

climate

Climate is the long-term pattern of weather in a particular area.

  • Best for: Grades 8+ (ages 13+)
  • Concepts: atmosphere, climate, climate change, humidity, precipitation, temperature, weather
yurt
Article
EDUCATION

yurt

A yurt is a portable, circular dwelling made of a lattice of flexible wood and covered in felt.

  • Best for: Grades 5+ (ages 10+)
  • Concepts: asia, dwellings, homes, mongolia, nomads, tents, yurts
keystone species
Article
EDUCATION

keystone species

A keystone species helps define an entire ecosystem. Without its keystone species, the ecosystem would be dramatically different or cease to exist altogether. 

  • Best for: Grades 6+ (ages 11+)
  • Concepts: animals, conservation, ecosystems, environment, habitats, keystone species, predators, trophic levels
GIS (geographic information system)
Article
EDUCATION

GIS (geographic information system)

A geographic information system (GIS) is a computer system for capturing, storing, checking, and displaying data related to positions on Earth’s surface.

  • Best for: Grades 6+ (ages 11+)
  • Concepts: cartography, geography, gis, industry, maps, technology
Arctic
Article
EDUCATION

Arctic

The Arctic is the northernmost region of the Earth

  • Best for: Grades 7+ (ages 12+)
  • Concepts: arctic, arctic circle, climate change, ecosystems, exploration, indigenous peoples, natural resources, north pole, sea ice, shipping, trade
Earth
Article
EDUCATION

Earth

Earth is the planet we live on, the third of eight planets in our solar system and the only known place in the universe to support life.

  • Best for: Grades 6+ (ages 11+)
  • Concepts: atmosphere, axes, biosphere, carbon cycle, core, crust, earth, geology, hydrosphere, lithosphere, mantle, moons, rotation, water cycle
continental divide
Article
EDUCATION

continental divide

A continental divide is an area of raised terrain that separates a continent’s river systems that feed to different basins.

  • Best for: Grades 6+ (ages 11+)
  • Concepts: continental divides, continents, drainage basins, rivers, watersheds
Earth Day
Article
EDUCATION

Earth Day

Earth Day is an annual celebration that honors the achievements of the environmental movement and raises awareness of the need to protect Earth’s natural resources for future generations. Earth Day is celebrated on April 22 in the United States and on either April 22 or the day the spring equi...

  • Best for: Grades 7+ (ages 12+)
  • Concepts: climate change, conservation, earth day, environment, holidays, international organizations
crater
Article
EDUCATION

crater

A crater is a bowl-shaped depression produced by the impact of a meteorite, volcanic activity, or an explosion.

  • Best for: Grades 6+ (ages 11+)
  • Concepts: craters, explosions, geology, landscape, maars, meteors, volcanoes
flood plain
Article
EDUCATION

flood plain

 A flood plain is a generally flat area of land next to a river or stream. 

  • Best for: Grades 6+ (ages 11+)
  • Concepts: flood plains, floods, landscape, rivers, urban planning
bluff
Article
EDUCATION

bluff

A bluff is a type of broad, rounded cliff.

  • Best for: Grades 4+ (ages 9+)
  • Concepts: beaches, bluffs, cliffs, erosion, flood plains, landscape
El Niño
Article
EDUCATION

El Niño

El Nino is a climate pattern that describes the unusual warming of surface waters in the eastern Pacific Ocean.

  • Best for: Grades 10+ (ages 15+)
  • Concepts: atmosphere, climate, currents, el niño, enso, la niña, pacific ocean, temperature, upwelling, weather, wind
core
Article
EDUCATION

core

Earth’s core is the very hot, very dense center of our planet.

  • Best for: Grades 6+ (ages 11+)
  • Concepts: core, earth, geology, iron, magnetism, physics
mantle
Article
EDUCATION

mantle

The mantle is the mostly-solid bulk of Earth's interior. The mantle lies between Earth's dense, super-heated core and its thin outer layer, the crust. The mantle is about 2,900 kilometers (1,802 miles) thick, and makes up a whopping 84% of Earth’s total volume.

  • Best for: Grades 5+ (ages 10+)
  • Concepts: asthenosphere, convection, geology, lithosphere, mantle, plate tectonics, rocks
ocean vent
Article
EDUCATION

ocean vent

An ocean vent is a fissure in the seafloor that spews hot, often toxic fluids and gases.

  • Best for: Grades 6+ (ages 11+)
  • Concepts: chemistry, geology, habitat, hydrothermal vents, ocean, ocean vents, plate tectonics, pressure, temperature
ocean trench
Article
EDUCATION

ocean trench

Ocean trenches are long, narrow depressions on the seafloor. These chasms are the deepest parts of the ocean—and some of the deepest natural spots on Earth. 

  • Best for: Grades 5+ (ages 10+)
  • Concepts: exploration, geology, lithosphere, marine biology, ocean, oceanography, ocean trenches, plate tectonics, seafloor, subduction, valleys
fold mountain
Article
EDUCATION

fold mountain

Fold mountains are created where two of Earth’s tectonic plates are pushed together. 

  • Best for: Grades 5+ (ages 10+)
  • Concepts: continents, crust, fold mountains, folds, geology, orogeny, plate tectonics
rift valley
Article
EDUCATION

rift valley

A rift valley is a lowland region that forms where Earth’s tectonic plates move apart, or rift.

  • Best for: Grades 6+ (ages 11+)
  • Concepts: continents, crust, geology, lakes, landscape, plate tectonics, rift valleys, seafloor spreading, valleys
seafloor spreading
Article
EDUCATION

seafloor spreading

Seafloor spreading is a geologic process in which tectonic plates—large slabs of Earth's lithosphere—split apart from each other.

  • Best for: Grades 6+ (ages 11+)
  • Concepts: crust, geology, mid-ocean ridges, ocean, plate tectonics, rift valleys, rocks, seafloor spreading, subduction
continental drift
Article
EDUCATION

continental drift

Continental drift describes one of the earliest ways geologists thought continents moved over time. Today, the theory of continental drift has been replaced by the science of plate tectonics.

  • Best for: Grades 5+ (ages 10+)
  • Concepts: continental drift, geology, pangaea, plate tectonics, rift valleys, seafloor spreading, subduction
crust
Article
EDUCATION

crust

The crust is the outermost layer of Earth.

  • Best for: Grades 5+ (ages 10+)
  • Concepts: crust, earth, geology, layers, ocean, plate tectonics, rocks, subduction
lithosphere
Article
EDUCATION

lithosphere

The lithosphere is the solid, outer part of the Earth, including the brittle upper portion of the mantle and the crust.

  • Best for: Grades 4+ (ages 9+)
  • Concepts: crust, geology, lithosphere, mantle, plate tectonics, rocks