The Seven Seas

• Second-graders may have heard the phrase "the seven seas" before in stories or movies. Here is their chance to learn what it really means. Teach your class the planet contains seven main seas, the North and South Pacific, the North and South Atlantic, Indian, Southern or Antarctic, and the Arctic oceans. Show students where the seven seas are on a map. Provide them with a photocopied map to color in with crayons and instruct them to color each ocean a different color to easily identify their locations.
  
  

Venomous Creatures

• An easy fact for second-graders to remember is that the most venomous animal in the ocean is the box jellyfish. Teach kids this species of jellyfish is primarily found in the waters off of Asia and Australia. Show pictures of the jellyfish to accompany your lesson and host a discussion about how a jellyfish stings its prey, as well as what happens when you are stung by a jellyfish.
  
  

Blue Ocean Myth Bust

• Tell second-graders to draw a picture of the ocean and color it in. Chances are your class will color in the ocean with a blue or sea-green crayon. Explain to students that the ocean is not really blue! In fact, the reason that the ocean looks blue is because it reflects the blue light rays that are produced by the sun. You can also unravel the phenomenon of why shallow ocean waters are lighter in color than the deep parts of the ocean. This is because light from the sun cannot reach below 3,280 feet, which is a half mile below the water.
  
  

Coral Reef

• Teach second-graders about what a coral reef is, and why it is a significant part of the ocean's habitat. Bring in a dried coral to show them and let them feel. Tell your students the largest coral reef is called the Great Barrier Reef, and is found in Australia. Share more interesting facts about the reef, such as that more than 30 species of whales and dolphins and 30 species of sea snakes visit or live in the Great Barrier Reef. For an activity, have kids draw pictures of a coral reef the way they imagine it to look underwater.