Fragile Reefs


Adjust your goggles and tighten your swim fins! Dive beneath the ocean surface to explore breathtakingly beautiful coral reefs and the thousands of species they shelter. Create a coral reef ecosystem in your own undersea diorama.


1. A coral reef resembles a large, busy city, with more species of sea creatures and plants than anywhere else in the ocean. Although a coral reef looks like a colorful rock formation on the sea floor, it’s really millions of tiny coral polyps living together in huge groups. Polyps are small, soft-bodied animals, about 1/4 inch wide. Some of them grow hard outer structures called exoskeletons. When the polyps die, they leave behind their exoskeletons. Live polyps attach themselves to the exoskeletons of dead polyps and so the reef builds. It takes about a year for a coral clump to grow outward 1 inch, so it takes a long time for a coral reef to form! There are about 230,000 square miles of coral reef in the world.

2. Polyps need warm, shallow, sea water to grow, so coral reefs are often near land. There are three main types of reefs. A fringing reef is attached to the shore. An atoll is a ring of coral formed around a sunken volcano. A barrier reef has a channel of water between it and the shore. Although all types of coral polyps grow in similar ways, the many different polyps form more than 2,500 different kinds of coral! It may resemble tree branches, the human brain, tiny pipes, fans, feathers, lace, or mushrooms. It may be bright pink, glowing orange, rich purple, or brilliant yellow. The warm, sunlit water and many hiding places of a coral reef attract thousands of different animals. Learn more about the creatures who live in a coral reef and then use your imagination to create your own diorama using ideas like these.

3. Use Crayola® Scissors to cut paper to fit inside a recycled box. With Crayola Markers, create the shallow, light-reflecting water you might find near a coral reef. Use Crayola Erasable Colored Pencils to draw small, brightly colored fish. Color with markers, cut out, and glue in several group formations, or schools, with Crayola School Glue. Glue the paper inside the shoe box, covering the sides, top, and bottom.

4. Create a coral reef with Crayola Model Magic. Use the neon and white modeling compound to create spirals and folds. Imprint interesting textures into the modeling material with household items. Create layers of textured and sculpted coral. The compound will stick to itself when fresh from the pack or may be glued after air drying. Use markers to create brightly colored shrimp, sea horses, or other tiny creatures. Cut out and glue to the coral. Add larger sea animals, such as angel fish or an octopus, to your seascape. Glue them around the edges of the box to add more depth to your diorama.

5. Explain to classmates, other students, or your families how coral reefs are in danger today due to overfishing, tourist activity, pollution, and global warming. Decide, as a group, on a possible course of action to prevent the loss of this very valuable habitat.

Safety Guidelines

Adult supervision is required for any arts & crafts project. Observe children closely and intervene as necessary to prevent potential safety problems and ensure appropriate use of arts and crafts materials. Some craft items, particularly beads and buttons, are potential choking hazards for young children. Avoid use of such small parts with children younger than 3 years. Craft items such as scissors, push pins and chenille sticks may have sharp points or edges. Avoid use of materials with sharp points by children younger than 4 years. Read all manufacturers' safety warnings before using arts and craft supplies.

Crayola Modeling Materials including Crayola Model Magic®, and Model Magic Fusion™, Crayola Air-Dry Clay, and Crayola Dough—

  • Keep away from open flames. Do not use to make candleholders, hot plates, trivets, or other similar objects that will be used or placed near fire and other heat sources.
  • Do not put in an oven, microwave, or kiln.
  • Do not make into vessels/containers that will hold unpackaged food.
  • The use of modeling material to make items that look like food is discouraged for children younger than age 5 to avoid their confusion with real food.
  • Unless sealed with a water-resistant glaze, do not make projects exposed to or immersed in water, such as boats or outdoor bird feeders. They would disintegrate when exposed to moisture.
  • Crayola Dough—contains gluten (wheat flour) as an ingredient.
  • Crayola Air-Dry Clay, Crayola Model Magic and Model Magic Fusion are gluten-free. However, they are produced on the same machinery as Crayola Dough which does contain gluten. Although the machines are cleaned prior to the start of each production run, there is a slight possibility that trace amounts of gluten from Crayola Dough may be present in the other modeling compound products. For information regarding specific ingredients or allergic concerns, please call our Consumer Affairs department at 1-800-272-9652 weekdays between 9 AM and 4 PM Eastern Standard Time.

Scissors—ATTENTION: The cutting edges of scissors are sharp and care should be taken whenever cutting or handling. Blunt-tip scissors should be used only by children 4 years and older. Pointed-tip scissors should be used only by children 6 years and older.


  • Find The Great Barrier Reef on a world map. It runs alongside the northeast coast of Queensland, Australia, and is the largest coral reef in the world. It stretches for 1,260 miles and is home to 4,000 species of shell fish, 2,000 species of fish, 500 species of seaweed, 500 species of coral, 16 species of sea snakes, and 6 species of sea turtles. Use this information to create math word problems using measurement, addition, subtraction, or estimation. Neatly write each problem on an index card. Number each card, then number a corresponding sheet of paper with the problem number and solution. Exchange cards, solving each problem in turn. Review problems and solutions together.
  • There are more kinds of animals in coral reefs than in any other earth habitat except rain forests. Choose different species to research, including microscopic algae and plankton, tiny animals like polyps, small animals, medium animals, and the largest predators. Draw and color your creature and note its prey and predators, how it protects itself, and how it catches its food. On a large wall, create a coral reef food chain, using yarn or paper strips to join one creature with the next. Start with algae and plankton and link each creature to the one it eats for energy and nourishment, ending with the largest predators such as sharks, manta rays, moray eels, and barracudas. Discuss what would happen if even one of the species in the food chain disappeared.
  • Assessment: Set aside a day on which dioramas are displayed around the perimeter of the room. Students walk around the room to see and hear each other’s diorama presentations that include: the type of coral reef depicted (atoll, fringing, or barrier), the type of coral, and the species of sea life represented. Allow time for students to ask questions of one another.

Related Lesson Plans

Lesson Plans

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crayola supplies
  • Erasable Colored Pencils
  • Markers
  • Model Magic®
  • No-Run School Glue
  • Pointed Tip Scissors
  • Giant Floor Pad
household supplies
  • textured items, such as sandpaper, screen, paper doilies, rubber sink mat
  • recycled cardboard box



  • Grades 4 to 6
  • Grades 7 to 12


  • Math
  • Science
  • Social Studies
  • Visual Arts


  • 30 to 60 minutes
  • Multiple Sessions


  • Students research to learn how coral reefs form, where they are located, and what plant and animal species find shelter in the reefs.

  • ?Students build and display a diorama to represent coral and animals that live in a coral reef.

  • ?Students participate in a discussion about what could be done to preserve the possible extinction of coral reefs.


Research Canada Standards
Research UK Standards
Research U.S. Standards