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Life in the Estuary – Grade 3

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Conceptual Scheme

Marine Aquaria


Successful Fieldtripping

Unit 1: Estuaries

   1. Where Rivers Meet the Sea
Students make a physical model of fresh and salt water layering in an estuary.

   2. Waterborne
A student reading with embedded questions about buoyancy of ships in different waters (e.g., fresh, salt, warm, cold).

   3. Plimsoll Floats
Students shape boats of modeling clay and test their boats’ abilities to carry a load in fresh water and in salt water.

   4. The Great Boat Float
A take home activity in which family members shape boats from aluminium foil and test buoyancy in fresh and salt water.

   5. Tide’s In/Tide’s Out
Students make a paper model which includes a graph of tide heights vs. time of day.

   6. Time and Tides
Students learn to read a tide table and to describe tidal differences using a 24 hour clock.

Unit 2: Plants and Crabs

   1. Whose Home?
Each student takes on a role (i.e., moon, water, eelgrass, crab…) enacting movements and behaviors representing the rise and fall of the tides.

   2. In the Eelgrass Bed
Students working in groups explore the eelgrass food web using a picture sheet, animal fact cards, and a reading with embedded questions.

   3. What Grows There?
Some plants can tolerate salt water. Students experiment by irrigating seedlings, some with fresh water, some with salty.

   4. Crab City
This reading provides a look at how humans make a living along our coasts and how marine animals are adapted to their environments.

   5. Crabs
This activity reviews material introduced in “Crab City” by providing a crab diagram for labeling, and questions about the diagram.

   6. What a Story!
Students order the mixed-up events in a story which follows the life of crabs from egg to our dinner table.

   7. Scrambled Crab
Students unscramble the mixed-up letters of crab terms, using the definitions of the terms as clues.

   8. Observing the Living Crab
Students observe crabs swimming, walking, digging, hunting, and eating.

Unit 3: Shrimp

   1. Shrimp – No Small Wonder
This reading focuses on shrimp anatomy and life cycle while continuing a look at how humans make a living along our coasts. Students make calculations regarding costs of shrimping.

   2. Only Half The Story
Students choose words about shrimp biology and fishing from a list to fill in blanks in a story.

   3. The Shrimp Boats Are A-Coming
Commercial shrimping provides livelihoods for many people. Students practice solving word problems, including challenge problems involving calculating averages and percents.

   4. How Hot Is Too Hot?
Students experiment to see how varying an environmental factor (temperature) affects hatching rate for brine shrimp eggs.

   5. Observing Brine Shrimp
Students use hand lenses and/or microscopes to observe compound eyes, gills, swimming behavior, response to light, and more.

Unit 4: Birds

   1. Who Flies There?
Students sort bird pictures into groups with common characteristics to gain an appreciation of diversity.

   2. An Assortment of Beaks
Students, equipped with one of four “beaks” (spoon, scissor, clothespin, or tweezer), take on the role of foraging birds and gather “food” types.

   3. Beaks and Feet
Students match a set of beak and feet cards, representing a variety of estuarine birds, with different food types and feeding areas.

   4. Who’s Hiding There?
Students search for camouflaged objects and relate their experience to bird survival in an estuary.

   5. Dangerous Journeys
Students assume the roles of ducks, wind storm, predators, and hunters to examine migration hazards.

   6. Migrating Down the Flyway
Students examine factors which limit or favor migration survival, measure migration distance on a map, then calculate migration duration.

Unit 5: Food Webs

   1. Who’s For Dinner?
Students play a card game in which each card represents an organism, and can only be “taken” by a card of the next food web level.

   2. Pyramids in the Marsh
Students calculate grams of food needed by each member of a marsh food chain/pyramid.

   3. Construct an Estuary
Students review adaptations and interactions by constructing a habitat model. Stuffed-crab plans included.

Unit 6: Clams

   1. Shell Sort
Students use size, shape, texture, color and weight to sort and classify shells. A student-made balance (ruler on an eraser) helps gauge weight.

   2. More Than a Few Clams
This reading, with crossword puzzle review, introduces clam biology, harvesting and marketing.

   3. Regulating the Harvest
This puzzle describes the reasons for rules such as filling in the holes made by clam diggers, and leaving oyster shells at the beach.

   4. Gooey Ducks?
Students use math skills to explore geoduck growth, population size, and rate and impact of harvesting.

   5. Insides Out
Students construct, label, and explore relationships between parts of a three dimensional paper model of a clam.

   6. Open Sesame
Steamed clams, from the beach or supermarket, give students an opportunity to match actual structures with models and drawings presented in preceding lessons.

   7. Write All About It! A Creative Clam Story
Students practice creative writing skills as they synthesize a clam story. The stage is set by showing a picture of a clam and its predator.

Unit 7: Oysters

   1. Oysters on the Half Shell
Students are full of insightful questions after being challenged to find a particular half shell, and then its mate, in a pile of oyster shells.

   2. Folding Oysters
Students put together oyster finger puppets while learning about oyster anatomy and physiology.

   3. The Oyster Story
A student reading with embedded questions about oyster aquaculture, harvesting and marketing provides a logical follow-up to “Oysters on the Half Shell”.

   4. Red Tides
Students learn what Red Tide is and isn’t, and how to avoid poisoning.

   5. Shellfish at Risk
Students play a board game matching contamination SOURCES, the PROBLEMS these lead to, and the SOLUTIONS people can employ.

   6. Red Sea Star Cafe
In this participatory simulation, students work as teams to “open” and “operate” a seafood restaurant.

Unit 8: People and Estuaries

   1. Where Have All the Salt Marshes Gone?
Students role play salt-marsh species faced with a shrinking habitat.

   2. National Estuaries of Significance
Students create metaphors denoting the features of estuaries, and use clues, such as salt or fresh water sources, to locate reserves on a map.

Production Credits

Below, you’ll find helpful resources for use with the above activities.

Unit 1: Estuaries

Activity 1 Where Rivers Meet the Sea
Estuary – a link to the sea
Estuary environments
Estuaries – a description

Activity 2 Waterborne
Root words

Activity 5 Tide’s In/Tide’s Out
Tidal chart activity

Unit 2: Plants and Crabs

Activity 2 In the Eelgrass Bed
Eelgrass bed slide show
Eelgrass bed slide show narrative

Activity 4 Crab City
Blue crab image

Unit 3: Shrimp

Activity 3 The Shrimp Boats Are A-Coming
Shrimp boat image

Activity 4 How Hot Is Too Hot?
A brine shrimp primer

Unit 4: Birds

Activity 4 Who’s Hiding There?
Shorebird outline masters

Unit 5: Food Webs

Activity 1 Who’s For Dinner?
Food chain cards 1
Food chain cards 2
How to find marine information

Unit 6: Clams

Activity 2 More Than a Few Clams
The clam business

Activity 4 Gooey Ducks?
Native American geoduck clam harvesting image
Diver suiting up image
Turn of the century clam collecting image
Geoduck clams ready to ship to market image
Geoduck dive boats
Geoduck clam image

Activity 7 Write All About It! A Creative Clam Story
The Clam Caper mystery

Unit 7:

Activity 3 The Oyster Story
Native American oyster harvesting
Working on the water
Oyster recovery
Oyster hatchery
An oyster disease story

Activity 4 Red Tides
Killer dinoflagellate fact sheet
Toxic red tides – why now?
Tracing a toxic tide
Reef fish

Activity 6 Red Sea Star Cafe
Red Sea Star slide show
Red Sea Star slide show narrative

Unit 8: People and Estuaries

Activity 2 National Estuaries of Significance
Chesapeake Bay – a model estuary guidebook
Chesapeake Bay Ecosystem
Geology Of The Chesapeake
Water & Sediments
Living Resources & Biological Communities
Food Production & Consumption
Preserving Chesapeake Bay: The Big Picture

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