Ocean Zones

In February we started our Ocean Zone Installation at school. Our display depicts each of the five ocean layers (sunlight zone, twilight zone, midnight zone, abyssal zone, and hadal zone/trenches). Students began by investigating the ways that certain species are physically and behaviorally adapted to survive in their particular zone (from sun-drenched plankton near the surface to the tube worms found in the darkest trenches below). Students studied the food chain and learned about microscopic plant-like and animal-like plankton. They found that phytoplankton are adapted to remain in the sunlight zone, making their own food thanks to the sun and serving as food for zooplankton. We were surprised to see, in photos of crab larva and reef fish larva, that some zooplankton spend only part of their life cycle as plankton and then turn into the adult crabs and beautiful reef fish that we more readily recognize. 

Students researched the exact depths that differentiate each layer (based on how much sunlight passes through) and they spent time at the library collecting photography books of sea life. After reading about the different types of creatures that are found in each zone, the class created some beautiful observational drawings and placed them on our mural in the correct zones.


Our students were especially interested in researching the coldest and darkest zone. Much of our research was focused on this lowest layer of the ocean, the Trenches or Hadal Zone. We spent time discussing the Challenger Deep (a.k.a. Mariana Trench), where some of the most primitive species on earth are found. Down there, instead of a food chain based on energy from the sun, we learned about a food chain based on the process of chemosynthesis. Students wondered how the trenches were made, which led us into a discussion of tectonic plate movements and subduction - a process leading to the formation of the deepest trench. Children were introduced (through video) to the scientists, past and present, who have ventured there and we marveled about the risks these explorers took in traveling to such amazing depths. Students were fascinated by the immense pressure and the types of vessels that are constructed for traveling to the Challenger Deep. While learning about bathymetry, and the tools that scientists use to make measurements of underwater depths, some of the students pointed out that the ocean floor maps looked similar to the topographical maps that they created last year! This astute observation is gratifying as they are making connections and beginning to understand and articulate the physical characteristics of the surface of our planet.

Moving Underwater

Inspired by our time observing Betta, Kindergartners began to discuss how different marine animals move their bodies. We noticed that our warrior fish swims by moving his tail from side to side. The fins positioned on either side of his body seemed to help him balance and steer. For swimming quickly, we saw that these side fins were held flat against his body but when the fish wanted to stop quickly, it extended its side fins out at the same time, using them as a break. We mentioned that most fish have several fins and we talked about how the fins positioned on the top and bottom of its body might prevent the fish from rocking back and forth, side to side.

We learned that some fish have a swim bladder (an air-filled sac inside the fishes body) that enables the fish to rise in the water. As our Betta comes up to the surface, he allows air to enter through his mouth, or from the bloodstream, into his swim bladder. As the bladder fills with air, the fish rises in the water. The fish sinks when he lets the air leave the bladder.

To demonstrate how a swim bladder works to allow a fish to move up and down we used:

A wide-mouth jar
tap water
2 glass marbles
2 round balloons

Using marbles and balloons we made two different sized swim bladders. We filled the jar with tap water and placed 1 marble inside each balloon. In the first balloon we tied a knot as close to the marble as possible. We inflated the second balloon slightly with air and tied the knot as close to the mouth of the balloon as possible. Then I asked students to predict what would happen when we dropped each balloon in the jar of water. Just as some of them had predicted, the inflated balloon floated and the deflated balloon sank to the bottom of the jar. The smaller, or more deflated the swim bladder, the deeper the fish can swim.

Not all marine animals have swim bladders though and we started to think about how and why marine animals might need to move around so much. Students said that fish move "to find food" and "to get away." After watching a few minutes of Oceans, we talked about how different marine species might be uniquely shaped to help their bodies move in very different ways through the water. Students were especially excited to watch the marine iguana move; we enjoyed seeing it make very deep dives and lumber along the rocky beach in the video. We noticed that its long tail and spiky fins seemed to help it to move quickly through the ocean and that its long sharp claws helped it to climb along the rocky shoreline.

Other animals shown in the video, such as the sea urchin, seem to hardly move at all. But when we watched very carefully, we saw that the sea urchin was actually crawling along the ocean floor. Pumping water into and out of its tubed feet, the urchin slowly glides along the sand. With their long spines we all agreed that other animals would be smart to stay away from the sea urchin!

We are looking forward to future investigations and are excited to learn about how other marine creatures move their bodies through the ocean.

Underwater Lab - Brick by Brick

In math class students were given the assignment of constructing a 24x8x10 ft. underwater research station. Using unit blocks, the students modeled a scaled down version that was able to accommodate 4 people and included a kitchen/living room, bedroom, and bathroom. They built a separate wet lab facility outside the main structure for experiments.

The group worked collaboratively, decided on the base design, and then recorded the necessary dimensions for calculating perimeter, area, and volume, for each room in their station. Their work also involved testing different methods of construction. After some trial and error, the students found that the strongest wall construction resulted when they used alternating brick orientations and that the weakest wall resulted when the brick seams were vertically aligned on top of one another other. Similar testing was done to shore up the corners and the students determined the best method for building and uniting strong intersecting walls.

Kindergartners would not be left out, they helped finish off the station by making signs and labels and thoughtfully affixed them around the underwater research vessel so that each room was clearly identified.

One 2nd grader suggested that the station be lit so we decided to include a lesson on electrical circuits. After a demonstration of open and closed circuits, and a discussion about volts and batteries, the students determined that they would be able to install only 3 small light bulbs (each requiring 2.33 volts) using the provided 9 V battery.

After the group worked together to measure out the appropriate wire lengths and determined the best placement for the lights within the station, we decided that another demonstration was in order.

We ventured outside and using relatively easy to find materials we fashioned a homemade light bulb. As electricity began to flow from our "super battery" it heated up our graphite (pencil refill) and it began to glow!

Wet Pet, Your Pet

A gorgeous warrior fish is the newest member to join our classroom. Kindergartners spent some time getting to know him last week. While making observations about his movements and behavior, they happily made suggestions for the name he should be given. Kindergartners noted that our fish is sometimes swimming in one spot near the surface while other times he can be found resting near the bottom in the rocks.

Therefore one suggested, "He should be named Rocky!"

Another Kindergartner felt the name "Rainbow" best suited him,  she said, "The sun shining through makes him change color."

They pointed out that he has two small fins near his gills that always move very quickly but that his tail doesn't move much while he is resting in one spot.

Students made some beautiful Betta fish drawings as they continued to debate names.

Regardless of the final name, they all seem to agree that the best part of taking care of their new classroom pet is when they are able to feed him his daily allotment of 3 freeze-dried bloodworms!

Coming Up for Air

After being away on maternity leave in September, I came back to Birches. 

In October we began a unit focused on the many different types of mammals that are alive today. Students learned about the traits that scientists use to classify a given animal as a mammal. Some of the distinguishing traits that we covered include: feeding young with mammary gland milk, possessing 3 middle ear bones and a single lower jaw bone, replacing teeth only once or not at all throughout their lifetime (rather than replacing teeth continually), having hair, and the ability to regulate their own body temperature (being warm-blooded).

After discussing these key features in detail, each student selected a mammal on which to research and complete individual reports. Some animals included the: grey wolf, coyote, raccoon, kangaroo rat, lemming, tree kangaroo, and chimpanzee.

Drawing from print and online sources, the students wrote their reports in a mystery book format and outlined unique facts that they found about their animals, distinguishing characteristics or clues, without revealing their mammals identity - that is - until the very end, as a lift-the-flap reveal with artwork. 

The kindergartners, on the other hand, worked collaboratively to create an A-Z mammal book. Using large print sources with beautiful photos, they selected mammals by their first letter and made drawings of each animal – devoting one mammal per page (for example: “ape” Aa, “bat” Bb, “cow” Cc, etc.). The book also gave them a nice opportunity to sound out letters and practice their letter writing skills.

In November and December, we continued our mammal investigations, shifting focus toward learning about marine mammals in particular. Students decided to create a magazine devoted to oceanographic issues and started working on writing persuasive articles. I set up a collaboration with Grace Young, an extraordinary MIT student who generously agreed to come visit us and tell us about her work. 

Through our connection with Grace, Birches students will follow Mission 31, an exploration led by filmmaker and oceanographic explorer Fabien Cousteau. For 31 days the mission, set in the Florida Keys National Marine Sanctuary, will be seen by students via Skype into the classroom. In April, students will be linked with scientists as they explore the underwater world using robots in the undersea lab Aquarius. 

Through creating their marine magazine, Birches students are learning how to write effectively persuasive pieces that urge readers to take an interest in caring about the ocean ecosystem and to act responsibly in harvesting natural resources therein. 

Testing Water Flow, Making Topographical Maps, and Experimenting with Buoyancy

May was another super month for continuing our water exploration.

We spent quite a few lessons testing the way water flows across and down different types of natural and man-made surfaces. It was fantastic watching the students make predictions about how water would flow along distinct geographical features that they selected around the school grounds. The students experimented by pouring water down asphalt inclines, grassy hills, ramps of small stones and large rocks, and over soil slopes. All this preliminary testing provided the students with a strong foundation on which to build their art installation at deCordova Sculpture Park in late May (More on that STEAM project!)

Since students were very interested in explaining the way mountains and valley's influence the flow of water I decided that we would use playdough to mold our own mini mountains and make individual topographical (topo) maps from them. Students found that topo maps are a great way to convey information about geographical features of a landscape and to visualize how water collects or flows around these physical elements. We discussed what these types of maps are especially useful for and students decided that topo maps are good for finding your way along "hiking trails" or while "canoeing and kayaking" and also for engineers who build roads and train tracks.

After molding their mini-mountains, the students measured the height and made slices through mountains at specific intervals. They then traced the outline of each layer of their cut mountain on a piece of paper - making rings that represented separate contour lines. (For details on how to do this lesson.)

Last month we also began exploring the physics of buoyancy. We started by defining density and buoyancy. To visualize density we talked about a cup of jelly beans and a cup of marshmallows and asked students to predict what would happen if they put each cup into the microwave. "They would melt!" responded the class. Yes, but the melted sugar and water from the jelly beans would almost fill the cup while the melted marshmallows would only fill the cup a little. Because the marshmallows are mostly air, they are less dense than the jelly beans. Next we discussed whether a jelly bean or marshmallow would be able to float in water. For those who enjoy hot chocolate with marshmallows in the winter time this was an easy question. We decided that for an object to be able to float it has to be "lighter" or have less density than the water...unless it is attached to something that helps it float, like a life jacket.

Next I asked if we could make a piece of clay float. I rolled a small piece of clay into a solid ball and asked the students to predict what would happen to the clay if we placed it in a tub of water. With contradictory responses, "It will sink." "It will float then sink.", "It will float." we decided to test it. After it sank, I gave each student a small square piece of plasticine modeling clay and asked them to try and make their clay float. Each student began to mold their piece into various shapes. They made cups, bowls, canoes, row boats, rafts, and even people. We had many "failures" before one student successfully produced a "boat". It was interesting that the students themselves came to define the clay as a boat only after they managed to make it float. Many students attempted to recreate the successful model but others kept to their original molds. At the end of class the students had decided that "No holes can be in the boat.", "Taller sides help it float.", "Make the clay thin.", "Keep the boat dry inside." and to "Put the boat into the tub carefully." They enjoyed the lesson so much so that we decided to continue with boats over the following Science Friday!

During the second session we began drawing comparisons by testing the buoyancy of clay boats to other objects. We compared wax paper, aluminum foil, and plastic weigh boats (of differing sizes) to the students' newly made clay molds. Students began by making predictions about which would have better buoyancy. After seeing the plastic float they wanted to test how much weight each of the boats could hold. Students used penny's to add weight to the clay and to the plastic boats and we were surprised to see that a few of the clay boats could hold just as much as the plastic boats.

Some students moved on to investigate whether they could make a piece of aluminum foil float. Using equal size pieces, a couple students made a loose ball while others made their foil into shapes that resembled their clay boat. Soon students were packing on as much as they could hold to see which boat would sink first. Near the end of class, students talked about how the shape of the sides determine how much cargo the boat will hold. We ran out of time but the class really wanted to test floating their boats in salt water!

Water, water, water

I'm hoping to catch up on a number of lesson updates...finally. I'm many weeks behind and now that it's school vacation week let's see if I can remember all the water-related activities!

In March we all participated in a water survey with our families at home. This is a fun 'What if?' game that the explores the many uses of water in the form of a questionnaire written by WaterPartners International.

Based on the questionnaire results, the students collaborated on a large scale collage, selecting images from several old National Geographic Magazines - depicting different uses of water - they cut these photos out for pasting onto a large poster board.

At the end of last month we had an introduction to storm drains and a visitor from the town water treatment center. The students were especially fascinated by the water pipes, gauges, meters, and large purification filters that our guest expert brought into the classroom.

One of the original questions posed by the students at the start of the semester was, 'How do we get clean water?' We were thrilled to have a geoscientist come talk to us about the process of water purification and to find out how the town provides us with safe drinking water. The students asked our guest many questions about the watershed and town well. In the future we hope to be able to visit the pumping facilities and treatment center for a first-hand look at the process.

In early April we started anticipating salamander egg laying season, more aptly termed 'Big Night'. The one special dark and rainy night, usually in early spring, when the temperature is just right (at or above 40 degrees), the ground is thawed, and the adult salamanders venture out from their underground hibernation dens to mate in nearby vernal pools.

Our science lesson involved making our own salamander life cycle booklet and learning to identify the different species of salamanders that we might expect see in our geographical area. Students were also very interested in the features that define a vernal (spring) pool vs. a pond, and in talking about what other animals live part of their lives in vernal pools.

We are very fortunate that our school has several nearby vernal pools, streams, and ponds for us to visit as we continue our water curriculum. So far the Redback salamander has been spotted by the students on several occasions and they were also lucky enough to see several sticks and twigs partially submerged in the water that were covered with gooey salamander eggs.

During another lesson we began learning about the different features that define ponds from lakes. We talked about the flora and fauna generally found within a pond habitat (drawing from their rich and recent experience of going on a nature walk with an expert conservationist!) and the microhabitats that can be found within different strata of a pond. After our discussion we decided to make our own mini-diorama of the pond ecosystem. The students painted a large cardboard box and created lily pads and other surface plants, insects, frogs, fish, worms, twigs, birds, and beavers all out of clay. It's a work in progress I hope to take a photo of the finished product to post here soon.