This section contains basic information about each shipboard learning station and ideas for integrating these concepts into your classroom.
- Discuss the concept of an estuary. Students should be aware that the Chesapeake Bay is a special environment because of its mixture of fresh and salt water (brackish). Why does the Bay have such a prolific variety of life? How would the tides and currents affect the distribution of salt and fresh water?
- Make A Model Estuary: Divide the class into 3 or 4 groups. Give each group of students a medicine dropper and 2 glass containers half filled with water. Put salt into one of the containers, which will represent the ocean. Have the students put 12 drops of food coloring into the salt water. The fresh water represents the water flowing from the many tributaries into the Bay. Ask the students what they think will happen when the two are mixed. Then use the droppers to have the students carefully add the colored salt water to the fresh water. Make sure they place the point of the dropper below the surface, and squeeze the solution out slowly. Have the students pass the dropper around so that everyone is involved. Do not swirl the water. Put a white piece of paper behind the glass to see what happens. Is this the expected result? Why did this occur? Which has a higher density, salt or fresh water?
- Copy and distribute the Water Quality page from the Student section. Briefly discuss the different things you will be testing for in the shipboard station. Special emphasis might be given to pH. pH shows the acidity or alkalinity of a solution by measuring the concentration of H+ and OH- ions. Introduce students to the pH scale, which runs from 1 – 14. Acids range from 1 – 6, with 1 being strongest. Bases range from 8 – 14, with 14 being the strongest. Neutral substances, like pure water, are found at pH 7.
- Give students the following list of substances, and see if they can guess which the pH of each. If possible, test a variety of substances using pH strips or a pH meter.
1 battery acid
2 lemon juice
3 dill pickles
4 acid rain
5 natural pH of rain
7 pure water
8 sea water
10 milk of magnesia
14 Drano sodium hydroxide
Water Quality – students may use wet chemistry, a colorimeter and refractometer to determine important water quality parameters, including dissolved oxygen, salinity, temperature, and pH. Data is recorded and made available for use at the Living Classrooms Foundation website. Students will take a hard copy back to their classroom.
- Students should know the basic definition of plankton. Copy and distribute the Plankton Station from the student section.
- Discuss the role of plankton in the food chain. It is important for students to have a basic concept of photosynthesis, and that plant plankton absorb and convert solar energy to begin the food chain. You can play a simple food web game by asking students to become different members of the Chesapeake Bay food chain, and to determine who would consume whom. See if students can figure out what should come before the plants in the chain (sunlight, CO2, nutrients).
- The Sea Soup books published by Tilbury House (2001) are full of wonderful information and pictures. There is a teacher guide too!
Plankton Studies – students tow for plankton and examine specimens under the video microscope. Organisms may be identified and recorded.
During this shipboard station, students will become familiar with charts and navigational tools.
- Copy and distribute the Navigation Station from the Student’s section.
- Familiarize students with the compass and basic directions (North = 0 and 360 degrees, East = 90 degrees, South = 180 degrees, and West = 270 degrees).
- It is beneficial if older students can come to this station with some preliminary knowledge of the idea that Distance = Speed x Time.
This formula makes sense if it is broken down by units. For example,
Distance in Miles
Speed in Miles Per Hour (M/H)
Time in Hours
Miles = Miles x Hour
- You can make up some questions according to your class level by using the simple formula D = S x T (and therefore T = D/S and S = D/T). For example:
- Pretend that you are driving a race car in the Indy 500. If you are driving at 180 MPH for 2 hours, how far have you traveled? D = S x T
D = 80 MPH x 2 H
D = 360 Miles
- You are the captain of a boat that is traveling at 5 knots (NOTE: 1 knot = 1 nautical mile per hour; 1 nautical mile = 1.15 land miles). After 3 hours, how many nautical miles have you covered? D = S x T
D = 5 knots x 3 hours (or 5 nautical miles/hour x 3 hours)
D = 15 nautical miles
Navigation – students learn the basics of navigation, how to plot a course, compass skills, and may even get to discuss speed-time-distance problems. This station has many math applications.
Students should come to the program with some preliminary knowledge of the oyster. Copy and distribute the Oyster Station from the Student section.
Oysters once were very important economically in this region. See how many historical industries your students can connect with the oyster. Here are some examples:
fishing : Oyster dredging was once one of the most profitable ways of working on the Bay
canning : The first canning patent was given for the canning of oysters in Baltimore
shucking houses : A business existed in the removal of oysters from their shells before canning
restaurants : Many area businesses specialized in seafood and raw bars
shipping : Skipjacks, pungies, and buy boats moved oysters around the Bay. After canning, oysters were shipped all over the country
boat building : During oyster boom years, many boat yards were created just to build skipjacks
garment industry : Oyster shells were used to make buttons
roadwork : Excess oyster shells were used to pave roadways
Oyster – Students examine and dissect live oysters while discussing the animal’s life cycle, habitat and importance to the Chesapeake Bay region. Traditional oystering boats and the history of oystering in the Chesapeake Bay are also discussed.
- Students should be aware of what kind of vessel they will be on, and what she was built to do. Copy and distribute the Helm Station handout from the student’s section. Copy and distribute the Fact Sheet and History documents for the vessel your students will be going on. The information in these documents may be reinforced with the Pre-voyage quiz.
- Help students become familiar with nautical terminology that they will use on the boat. Set up your classroom as a ship and try to only use maritime language. For example, the front of the room can be the bow, the rear of the room the stern, the left side port and the right side starboard. Students can make labels to put in appropriate places.
- Discuss the importance of the lookout on board a ship. Students will act as lookouts as they steer the ship and they must realize the significance of this position. The helm crew is responsible for the safety of everyone on the boat. Are there lines in the water to tell boats where to drive like there are on the roads? (NO – but there are buoys and channel markers). Do you think there is much boating traffic in Baltimore harbor? (YES). Many large ships travel in and out of the harbor, and the lookout will be responsible for reporting all traffic to the captain.
Helm – students steer the vessel with the assistance of the Captain. This involves correlation with the navigators, steering a compass course, completing the ship’s log, standing lookout and understanding of basic rules of the road.
- Acquaint students with the definition of buoyancy. Copy and distribute the Buoyancy page from the student section.
- Ask students to consider what materials boats are made of. What were boats made of in the 1800s? What kinds of things are boats constructed from today? See how many materials they can list (wood, fiberglass, plastic, steel, cement, aluminum, rubber). How well do these substances float? Test them in your classroom.
- As part of their understanding of buoyancy, students should know about displacement. What happens to the level of water in the bathtub when you get into it? It rises – in effect, some of the water moves out of the way to make room for your body. In other words, you displace the water. How much will the water level rise? Will it rise more if a baby or an adult gets into the tub? The adult will displace more water than the baby. This is because the volume of water displaced is equal to the volume of the displacing body. You can do an experiment to prove this:
- Place 300ml of water in a graduated cylinder. Weigh a stick of wood (like a dowel) on a metric scale. Place the stick into the graduated cylinder and note the rise in water level. If 1ml of water = 1g, then the weight of the stick is equal to the number of ml the water level rose. The weights of large vessels are often given in tons of displacement.
Bouyancy – students will explore the physics of buoyancy, gravity, and displacement by building boats out of simple materials, such as aluminum foil, newspaper, and duct tape. These boats will be entered in the Buoyancy Challenge, where weights are added to the vessels to see which is the most buoyant.
- Copy and distribute the Sail Theory Station from the Student section.
- Discuss the fact that Lady Maryland is a Pungy Schooner similar to those that historically sailed on the Chesapeake, before the days of the internal combustion engine. These ships were tools that utilized the power of wind to move cargo from port to port. Likewise Sigsbee is a skipjack, which traditionally had a push boat containing an engine to power the vessel when it was not actively harvesting oysters.
- Students should understand the benefits of fore-and-aft rigged sails (sails rigged parallel to the keel). Benefits are that the boat can sail to windward, or towards the wind. Compare these to square sails on square-rigged ships (such as the USS Constellation, in the Inner Harbor), which can only sail downwind. This information is contained in the Sail Theory Station section.
- Using the “Tacking Up Wind” document in the Sail Theory Station, discuss the way in which the boat needs to orient itself in relation to the wind in order to accomplish the tacking maneuver. While onboard ask the students to take note of when the maneuver occurs.
Copy and distribute the Mechanical Advantage Station from the student section.
- Students should be familiar with a simple definition of a machine. A machine is any device that helps us do work. All around us are hundreds of examples of machines people use to make work easier. Have your class look around for examples. Compile a list and then place each machine into one of the following categories: inclined plane, block and tackle, and lever. Even the human arm is a machine (a lever!) What kind of mechanical advantage do students expect to see on the boat?
- How do levers make work easier? Do an experiment in class to illustrate. Take a crowbar. Why is it easier to pry things apart with a crowbar than with your own hands? Ask your class to think of other examples of levers. Some work by pushing downward (examples: crowbar, oars, seesaw) and others by pulling up. How does the length of the lever affect the ease of the job? Depending on the level of your students, you may want to discuss the principles behind the lever-force, fulcrum, and resistance.
- How do blocks and tackle make work easier? A block (pulley) and tackle (rope) is a system used to increase your hauling power. Blocks can be made of one or multiple sheaves (pulleys) and the advantage gained can be determined by counting the number of pieces of rope at the moving block (thus, a double block (2 sheaves) has four pieces of rope at the block (2 in and 2 out). This is a 4-part advantage and requires only one quarter of the effort to move a weight. Tackles can be rigged “to advantage”, where the direction you pull the line is the same as the direction that you move the weight. They can also be rigged “to disadvantage”, where the pull is opposite to the way the weight will move. Tackles and levers are the underlying principles in all the large cranes you will see along the shoreline and on the decks of large freighters during your voyage.
Salt Wedge/Estuary – students perform an experiment to see what happens when fresh water from rivers meets with salt water from the ocean in an estuarine environment.
Estuarine Life – students observe animals caught in the trawl net. They use dichotomous keys to identify the animals and have the opportunity to learn about each animal’s characteristics.
Between station rotations students will observe the workings of the harbor and local points of historical interest. These may include: Ft. McHenry, Domino Sugar, the US Naval Hospital Ship Comfort and the Dundalk and the Seagirt Marine terminals. After the morning rotations, students enjoy lunch on deck.
The afternoon aboard the vessels centers on trawl fishing and the examination of the organisms caught in the net. Students are introduced to this method of fishing and the parts of the net and then help set and retrieve the trawl. After the fish are brought aboard, groups of students are given different species and challenged with identifying the animals using dichotomous keys. The shipboard experience concludes with a review and correlation of the day’s events. Students may return to school with the water quality data, plankton record, and a trawl data record for further classroom studies.
Other options for shipboard stations may include:
- Weather – students record weather observations, including wind speed and direction, wave height, temperature, barometric readings, relative humidity and cloud cover, and are introduced to the basics of how weather works.
- Watershed Run-Off – students learn first-hand about run-off and watershed issues as they apply strategies to a working urban/rural run-off model.
Sail Theory- students will gain a basic understanding of what makes a sailing vessel work while using a working model of Lady Maryland to discuss ballast, buoyancy, and Bernoulli’s Principle. The participants in this station are also responsible for carrying out the procedures necessary to sail Lady Maryland.
- Oyster Reef Restoration Project¬ Students aboard Sigsbee will dredge for oysters on a restored oyster bar near Ft. Carroll. In the afternoon, they will have the chance to help the crew collect data and assess the health of the oyster bar by examining oyster spat and other animals that inhabit the oyster bar community.