Elementary School Science

Input:
What is the most important content in this lesson?
To reach this lesson’s objective, students need to understand:

• The two types of water found on the Earth’s surface: saltwater and freshwater.

• The characteristics of freshwater regions and saltwater regions.

• What types of plants and animals can be found in freshwater regions and saltwater regions.

• The location of the major oceans of the world.

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How will the learning of this content be facilitated?

• The teacher will begin the class by showing the video, “Celebrate World Ocean Day.” (Source: https://www.youtube.com/watch?v=5ANCpQ-bpmo). The video is about 2 minutes long and was created by the NOAA National Ocean Service to celebrate World Ocean Day. The video provides excellent facts about the ocean. After the video, the teacher should begin a discussion about the content/ what the students observed.

• Next, the teacher should review the “Our Earth’s Biomes” worksheet [from the lesson, “Biomes”] with the students. Once the review is over, the teacher should explain to the students that today they are going to learn about the aquatic biome.

• Next, the teacher will hand out the worksheet “The Aquatic Biome” worksheet packet. If it is possible, project each worksheet of the “The Aquatic Biome” worksheet packet onto the board using a projector or put into a PowerPoint document and project. The teacher should begin with the “Saltwater vs. Freshwater” worksheet. As the teacher discusses the characteristics of each, the students will fill in the chart. From this activity, the students will learn about the characteristics of freshwater and saltwater.

**The student worksheet does not contain all of this information. Use this as a guide to help explain the aquatic biome more in depth to the students**

• The aquatic biome is the largest biome in the world.

• 75% of the Earth’s surface is covered with water.

• Water comes in the form of oceans, lakes, rivers, ponds, streams, bogs, swamps, etc.

• The Earth’s water is divided into saltwater regions and freshwater regions.

• Saltwater regions include oceans, coral reefs, and estuaries, which is the largest ecosystem of the Earth.

• Freshwater regions include ponds, lakes, streams, rivers, and wetlands.

• The main difference between saltwater regions and freshwater regions is the content of salt in the water.

• Saltwater regions contain a high salinity (salt) content/ sodium chloride.

• In one liter of saltwater, there is 35 grams of salt.

• Freshwater regions contain salinity as well, but the content isn’t as high as the saltwater region. The salt content in freshwater is less than 1%.

• If you taste water from the ocean, you can taste the salt. If you taste water from a lake, you do not taste salt.

• The ocean has a higher density than freshwater because of the amount of salt.

• Some plants and animals cannot survive in fresh water if they are meant to live in saltwater and vice-versa.

• Saltwater is not used as water source for humans because of the high salt content. Drinking water with salt can cause dehydration in humans.

• Freshwater regions are often found near land; however, this increases the risk of contamination from chemicals, pollutants, and other substances.

 

Information Sources:

​https://www.reference.com/science/difference-between-salt-water-fresh-water-1d2f2418ecef324#

http://www.food-info.net/uk/qa/qa-wat06.htm

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• Next, the teacher should review the “What is Saltwater?” worksheet. As the teacher explains, the students should fill in their worksheet.

**The student worksheet does not contain all of this information. Use this as a guide to help explain the saltwater region more in depth to the students**

• Saltwater regions, also known as marine regions, are made up of oceans, coral reefs, and estuaries.

• Coral reefs are barriers of coral that are on the ocean floor.

• An estuary is a stream or river that merges with the ocean. The merging creates a combination of salt and fresh water, which results in a unique salt concentration.

• The Earth has five major oceans (The students will learn the location of these oceans in a future worksheet): Pacific, Atlantic, Indian, Arctic, and Southern. There are also smaller gulfs and bays.

• There are over one million different plant and animal species found in saltwater.

• Algae, although may not seem like it is, is very important. Algae takes in the carbon dioxide and through photosynthesis, provides much of the Earth’s oxygen supply.

• In the ocean, you can find: whales, mollusks, octopi, fish, sea stars, sharks, varieties of algae, seahorses, jellyfish, seaweed, fungus, sea urchins, coral, seaweed, and plankton.

• In estuaries, you can find: worms, oysters, crabs, and fowl such as, herons, geese, and ducks.

• The ocean is divided into three vertical zones: euphotic zone (top), disphotic zone (middle), aphotic zone (bottom)

  • Euphotic Zone: top zone of the ocean where light can penetrate through.

  • Disphotic Zone: the middle zone of the ocean where light cannot penetrate through. This area resembles an Earth’s twilight.

  • Aphotic Zone: the bottom zone of the ocean, also known as the “deep sea”. This is the deepest, coldest, and darkest part of the ocean.

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Information Sources:

http://kids.nceas.ucsb.edu/biomes/marine.html

http://www.ucmp.berkeley.edu/glossary/gloss5/biome/aquatic.html

http://www.kidzworld.com/article/1951-biomes-of-the-world-aquatic 

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• Next, the teacher should review the “What is Freshwater?” worksheet. As the teacher explains, the students should fill in their worksheet

**The student worksheet does not contain all of this information. Use this as a guide to help explain the freshwater region more in depth to the students**

• Freshwater regions are made up of ponds, lakes, rivers, streams, and wetlands.

• Freshwater regions can be divided into: standing bodies of water (ponds, lakes, and wetlands) and floating bodies of water (rivers and streams).

• Ponds and lakes may look the same, however, they are very different. Ponds are often the result of rain/ rainy seasons and can be temporary. Lakes, however, stay around for hundreds of years.

• Streams are also the result of rain/ rainy seasons. They can also be the result of melted snow and ice. Streams form when a channel is created by water flowing downhill. These channels become capable of carrying water, resulting in the formation of a stream.

• Rivers are formed from streams. As streams form and meet up, they begin to create larger streams, which eventually turn into rivers.

• Wetlands can be formed in a variety of different ways. Some wetlands are the result of coastal flooding. Some are the result of glaciers, erosion, and natural forces such as, sinkholes. Some are the result of beaver dams. Other wetlands are the result of human engineering—such as, irrigation systems, and dam and highway construction.

• Freshwater regions contain a very small amount of salt, and therefore, if you happen to taste water from a lake, you will not taste salt.

• Plants in the freshwater regions are very important to the animals that live there.

• Animals and plants you can find in ponds and lakes include: frogs, snails, insects, snakes, salamanders, turtles, lily pads, and algae.

• Animals and plants you can find in streams and rivers include: trout, salmon, fungi, catfish, and dragonflies.

• Animals and plants you can find in wetlands include: water scorpions, bullfrog, beavers, alligators, herons, and cattails.

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Information Sources:

https://www.reference.com/science/streams-formed-fc92634363d90017

http://www.dkfindout.com/us/earth/rivers/how-do-rivers-form/

https://www.nps.gov/subjects/wetlands/how.htm

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• The last worksheet the teacher should review is the “Oceans of the World” worksheet. This worksheet is used just to show the students where the Earth’s major oceans are located.

**Refer to the teacher copy of the worksheet**

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• After the worksheet packet is reviewed, the students will participate in an activity called “Help Me Get Home!” The students will work in groups of three. Each student will get a “Help Me Get Home!” worksheet. On desks around the room will be different pictures of animals (mix the animals up—don’t put all of the ocean together). Each desk will have three animals or plants that have gotten lost and need to find their way home. The students will work together as a group to determine where the animal or plant lives and color in the correct block on their worksheet. Allow the students to work for about 10-15 minutes. Reconvene and discuss when the students are finished.

• The final assessment will be for the students to answer the question:

Think about what you learned in class today. What is the main difference between saltwater and freshwater regions? What percentage of the Earth’s surface is covered with water? Can saltwater be used as a source for humans? Why or why not? How many zones is the ocean divided into? How many categories is the freshwater region divided into? What are they called?