Mountains, Hills, Plains, Rivers, and Lakes: First Grade Social

Landforms and bodies of water are the natural shapes and aquatic features that sculpt the surface of our planet into breathtaking landscapes.

What Are Landforms?

A landform is a natural physical feature on the surface of the Earth. Landforms were not built by human bulldozers or tools; they were carved over millions of years by natural forces like wind, rain, rushing water, and heat deep inside the Earth.

+-------------------------------------------------------------+
|                     COMMON EARTH LANDFORMS                  |
+-------------+-----------------------------------------------+
|  Mountain   | Very tall, steep, rocky land with a peak      |
|  Hill       | Raised mound of land, smaller than a mountain |
|  Plain      | Broad, flat, open area of low grassy land     |
|  Plateau    | High flat-topped table of land                |
|  Valley     | Low land nestled between mountains or hills   |
+-------------+-----------------------------------------------+

Mountains: The Giants of the Earth

A mountain is the highest kind of landform. Mountains rise steeply high into the sky and usually have sharp, rocky peaks called summits. Because the air gets colder the higher you climb, mountain peaks are often covered in white snow even during summer months.

                     MOUNTAIN PROFILE
                          /                         /  \  <--- Snowy Peak (Summit)
                        /                           /                            /   /\             ___________/   /  \   \___________
              Lowland / Valley

Hills: Gentle Slopes

Hills are mounds of raised land, but they are shorter, rounder, and less steep than mountains. Hills are usually covered with grass, wildflowers, and trees, making them easy to walk up and down. A hill does not have a sharp rocky peak; it has a gentle, rounded top.

Plains and Valleys

A plain is a wide, flat stretch of open land that extends as far as the eye can see. Because the soil on plains is often rich and deep, plains are ideal places for growing wheat, corn, and oats, and for grazing cattle.

A valley is a low area of land situated between hills or mountains. Valleys are often shaped like a letter "V" or a letter "U," carved by flowing streams or creeping sheets of ancient ice called glaciers. Because water flows downhill into valleys, they are lush and fertile places where towns often settle.

               VALLEY BETWEEN TWO MOUNTAINS

        /\                              /       /  \    MOUNTAIN    MOUNTAIN    /        /    \                          /         /      \       [ VALLEY ]       /          /        \____  River runs  ____/                          \___________/

Exploring Bodies of Water

Just as Earth has diverse land shapes, it has diverse bodies of water, ranging from rushing freshwater streams to calm blue lakes.

+---------------------+---------------------------------------+
| BODY OF WATER       | WATER TYPE AND MOVEMENT               |
+---------------------+---------------------------------------+
| Stream / Creek      | Small, shallow, moving freshwater     |
| River               | Large, deep, moving freshwater flowing|
|                     | toward an ocean or lake               |
| Pond                | Small, still freshwater surrounded    |
|                     | completely by land                    |
| Lake                | Large, deep, still freshwater         |
|                     | surrounded completely by land         |
| Ocean               | Vast, salty water covering Earth      |
+---------------------+---------------------------------------+

Flowing Waters: Streams and Rivers

Water is always on the move. Rain falls on mountain peaks and trickles down in tiny rivulets. These rivulets join together to form babbling brooks and streams.

When many streams flow together, they become a river. A river is a large, powerful ribbon of moving freshwater that winds across plains and valleys, carrying water and nutrients until it empties into a lake or an ocean.

                     RIVER FLOW DIAGRAM

    [ High Mountain Snow ]
              |
              v (Melts into)
    [ Babbling Brook / Stream ]
              |
              v (Gathers into)
    [ Winding River ]
              |
              v (Empties into)
    [ Vast Blue Ocean ]

Still Waters: Ponds and Lakes

Not all water flows in long lines. Some water gathers in hollow depressions in the land.

A pond is a small body of still freshwater surrounded completely by land. Ponds are shallow enough that sunlight reaches the bottom, allowing water lilies and cattails to grow all across them.

A lake is much larger and deeper than a pond. Lakes are surrounded by land on all sides. Some lakes, such as the Great Lakes in North America, are so vast that when you stand on one shore, you cannot see the other side!

How Land and Water Shape Where People Live

Throughout history, people have chosen where to build towns based on landforms and water.

Humans need clean freshwater to drink, cook, and wash. Farmers settle in flat plains with fertile soil to plant crops. Cities grow along deep rivers where boats can transport food and manufactured goods to distant markets.

Exercises and Review

Exercise 1: Describe the main differences between a mountain and a hill.

Exercise 1 Solution: A mountain is very tall with steep, rocky slopes and sharp peaks that are often covered in snow, while a hill is much shorter with gentle, rounded slopes that are usually covered in grass and trees.

Exercise 2: What is the difference between a river and a lake?

Exercise 2 Solution: A river is a moving ribbon of freshwater that flows across the land toward an ocean or lake, while a lake is a large body of still freshwater that is completely surrounded by land on all sides.