Skip to content

Encyclopedic Entries

Filters

Showing results 76 - 100 of 132

Africa: Physical Geography
Article
EDUCATION

Africa: Physical Geography

Africa has an array of diverse ecosystems, from sandy deserts to lush rain forests.

  • Best for: Grades 6 and up (ages 11 and up)
  • Concepts: africa, continents, deserts, lakes, mountains, physical geography, rain forests, sahara, sahel, savannas
herding
Article
EDUCATION

herding

Encyclopedic entry. Herding is the practice of caring for roaming groups of livestock over a large area.

  • Best for: Grades 5 and up (ages 10 and up)
  • Concepts: agriculture, cattle, cowboys, domestication, herding, livestock, nomads, pastoralism, ranching, transhumance
ranching
Article
EDUCATION

ranching

Encyclopedic entry. Ranching is the practice of raising herds of animals on large tracts of land. Ranchers commonly raise grazing animals such as cattle and sheep.

  • Best for: Grades 5 and up (ages 10 and up)
  • Concepts: agriculture, animals, cattle, cowboys, domestication, grazing, herds, horses, livestock, outback, pampas, prairies, ranching, rural areas, sheep
flood
Article
EDUCATION

flood

A flood happens when water overflows or soaks land that is normally dry. There are few places on Earth where people don’t need to be concerned about flooding.

  • Best for: Grades 5 and up (ages 10 and up)
  • Concepts: floods, natural disasters, ocean, precipitation, rivers, storm surges, tsunamis, water
desert
Article
EDUCATION

desert

Deserts are areas that receive very little precipitation.

  • Best for: Grades 6 and up (ages 11 and up)
  • Concepts: adaptation, agriculture, basins, civilizations, climate, desertification, deserts, global warming, landscape, precipitation, rain shadows, temperature
archaeology
Article
EDUCATION

archaeology

Archaeology is the study of the human past using material remains. These remains can be any objects that people created, modified, or used.

  • Best for: Grades 3 and up (ages 8 and up)
  • Concepts: anthropology, archaeology, artifacts, features, field work, history
watershed
Article
EDUCATION

watershed

A watershed is an entire river system—an area drained by a river and its tributaries. It is sometimes called a drainage basin.

  • Best for: Grades 4 and up (ages 9 and up)
  • Concepts: divides, drainage basins, rivers, tributaries, watersheds
reef
Article
EDUCATION

reef

A reef is a ridge of material at or near the surface of the ocean. There are natural and artificial reefs.

  • Best for: Grades 6 and up (ages 11 and up)
  • Concepts: aquaculture, atolls, climate change, coasts, coral, coral bleaching, ecosystems, fishing, great barrier reef, islands, minerals, oysters, pollution, reefs, rocks, sand, tourism
growing season
Article
EDUCATION

growing season

Encyclopedic entry. A growing season is the period of the year when crops and other plants grow successfully. The length of a growing season varies from place to place.

  • Best for: Grades 5 and up (ages 10 and up)
  • Concepts: agriculture, crops, growing seasons, plants, seasons
grain
Article
EDUCATION

grain

Grain is the harvested seed of grasses such as wheat, oats, rice, and corn. Other important grains include sorghum, millet, rye, and barley.

  • Best for: Grades 5 and up (ages 10 and up)
  • Concepts: agriculture, cereals, crops, food, food staples, grain, livestock, wheat
Continent
Article
EDUCATION

Continent

A continent is one of Earth’s seven main divisions of land. The continents are, from largest to smallest: Asia, Africa, North America, South America, Antarctica, Europe, and Australia.

  • Best for: Grades 4 and up (ages 9 and up)
  • Concepts: africa, antarctica, asia, continents, europe, north america, oceania, south america, tectonic activity
Lake
Article
EDUCATION

Lake

A lake is a body of water that is surrounded by land. There are millions of lakes in the world.

  • Best for: Grades 7 and up (ages 12 and up)
  • Concepts: basins, freshwater, glaciers, lakes, limnology, pollution, water cycle, watersheds
gulf
Article
EDUCATION

gulf

Encyclopedic entry. A gulf is portion of the ocean that penetrates land. Gulfs vary greatly in size, shape, and depth.

  • Best for: Grades 4 and up (ages 9 and up)
  • Concepts: bays, gulfs, ocean, seas
Crops
Article
EDUCATION

Crops

A crop is a plant or plant product that can be grown and harvested for profit or subsistence. By use, crops fall into six categories: food crops, feed crops, fiber crops, oil crops, ornamental crops, and industrial crops.

  • Best for: Grades 5 - 8 (ages 10 - 14)
  • Concepts: agriculture, biodiversity, crops, farming, food, gmos, harvesting, plants, seed banks
pollution
Article
EDUCATION

pollution

Pollution is the introduction of harmful materials into the environment. These harmful materials are called pollutants.

  • Best for: Grades 6 and up (ages 11 and up)
  • Concepts: agriculture, air pollution, algal blooms, chemicals, conservation, dead zones, economics, fertilizer, garbage, industry, landfills, land pollution, oil, pesticides, pollution, runoff, smog, trash, water pollution
Census
Article
EDUCATION

Census

A census counts the population of a nation, state, or other geographic region. It records information about the population’s characteristics, such as age, sex, and occupation.

  • Best for: Grades 9 and up (ages 14 and up)
  • Concepts: censuses, demographics, development, government, population, quantitative data, questionnaires, taxes
dike
Article
EDUCATION

dike

A dike is a barrier used to regulate or hold back water from a river, lake, or even the ocean. In geology, a dike is a large slab of rock that cuts through another type of rock.

  • Best for: Grades 4 and up (ages 9 and up)
  • Concepts: dikes, floods, geology, landscape, levees, rocks, water
loess
Article
EDUCATION

loess

Encyclopedic entry. In some parts of the world, windblown dust and silt blanket the land. This layer of fine, mineral-rich material is called loess.

  • Best for: Grades 4 and up (ages 9 and up)
  • Concepts: dust, earth, erosion, fertility, glaciers, loess, soil
U.S. Census
Article
EDUCATION

U.S. Census

Encyclopedic entry. The U.S. Census counts every resident in the United States. It is required by the United States Constitution to take place every 10 years.

  • Best for: Grades 9 and up (ages 14 and up)
  • Concepts: american community survey, apportionment, censuses, congress, demographics, economics, government, measurement, population, quantitative data, u.s. census
border
Article
EDUCATION

border

Encyclopedic entry. A border is a real or artificial line that separates geographic areas. Borders are political boundaries.

  • Best for: Grades 5 and up (ages 10 and up)
  • Concepts: borders, boundaries, countries, economics, maps, nations, politics
biosphere
Article
EDUCATION

biosphere

The biosphere is made up of the parts of Earth where life exists. The biosphere extends from the deepest root systems of trees to the dark environment of ocean trenches, to lush rain forests and high mountaintops.

  • Best for: Grades 5 and up (ages 10 and up)
  • Concepts: atmosphere, biosphere, biosphere reserves, earth, ecosystems, hydrosphere, landscape, lithosphere, ocean
Environmental Refugee
Article
EDUCATION

Environmental Refugee

Climate refugees are people who must leave their homes and communities because of the effects of climate change and global warming. Climate refugees belong to a larger group of immigrants known as environmental refugees.

  • Best for: Grades 8 and up (ages 13 and up)
  • Concepts: climate change, climate refugees, desertification, drought, economics, global warming, immigration, migration, politics, refugees, sea level rise
oasis
Article
EDUCATION

oasis

Encyclopedic entry. An oasis is an area made fertile by a source of freshwater in an otherwise dry and arid region. Oases (more than one oasis) are irrigated by natural springs or other underground water sources.

  • Best for: Grades 9 and up (ages 14 and up)
  • Concepts: agriculture, deserts, fertility, freshwater, oases
county
Article
EDUCATION

county

Encyclopedic entry. A county is a territorial division and a unit of local government in some countries. Counties are usually made up of cities, towns, or rural populations.

  • Best for: Grades 4 and up (ages 9 and up)
  • Concepts: area, counties, county seats, geography, government
steppe
Article
EDUCATION

steppe

A steppe is a dry, grassy plain. Steppes occur in temperate climates, which lie between the tropics and polar regions.

  • Best for: Grades 6 and up (ages 11 and up)
  • Concepts: grasses, grasslands, great plains, pastures, plains, prairies, steppes, trade