Earth's Properties and Materials

1. Different materials, such as rocks, minerals, and soil make up earth.
   1. Observe and identify earth materials such as rocks and soils.
   2. Compare and contrast earth materials such as soils and sand, through simple
      observation and investigation.
   3. Recognize that fossils are the remains or evidence of once living plants and animals. Fossils provide clues about past environmental conditions.

Atmosphere and Water

1. Air:
   1. is a mixture of gases.
   2. can be measured.
   3. moves around us as wind.
2. Water:
   1. Sources: oceans, lakes, rivers, streams, glaciers and precipitation.
   2. Uses: drinking, recreation, bathing, transportation, solvent.
   3. Forms: solid, liquid, gas.
      1. Water can be a solid, liquid or gas and can change back and forth from one form to another.
      2. When liquid water disappears, it turns into a gas (vapor) in the air and can reappear as a liquid when cooled, or as a solid if cooled below the freezing point.
      3. Water evaporates from the surface of earth, rises and cools, condenses into rain or snow, and falls again to the surface. The water falling on the land collects in rivers, lakes, soil, and porous layers of rock. Much of it flows back into the ocean. This is known as the water cycle.
   4. Using maps, charts, graphs, and other visual materials, sources and uses of water and its forms can be identified.
3. Weather can be described in measurable quantities.
   1. To fully understand weather, it is important to observe, collect, and record data daily.
   2. Temperature, wind direction and speed, precipitation and types of cloud cover are examples of measurable quantities of weather data.
   3. Clouds are masses of water droplets or ice crystals that hang over earth.
   4. Rain, snow and other precipitation come from clouds but not all clouds produce precipitation.

Processes that Shape Earth

1. Earth's materials are formed in different ways.
   1. For example: erosion, weathering, and sometimes by rapid processes such as landslides, volcanic eruptions, and earthquakes.
   2. Fossils are sometimes revealed by erosion.

How We Study Earth

1. Observe, collect and record sample materials that describe features of the local environment (e.g., rocks and soil).
2. Maps are used to present information about earth (e.g., land features and weather conditions).