To dam or not to dam?

We've spent the week discussing dams, which, as it turns out, are pretty controversial structures. 

We began with the reading of a hypothetical scenario in a hypothetical town: The tiny town of Rocksburg (population: 900) sits on the (also fictional) Jones River. The citizens are considering approving the construction of a dam on the river two miles upstream from the town. We spent a lot of time mulling over the ramifications of such a structure. 

There are many pros to this idea. For example, it would provide the area with a clean power supply. It would generate a number of jobs in the area, while stimulating the local economy by increasing tax revenues and increasing tourism. The lake created by the dam would help control flooding, provide inexpensive irrigation for farmers, and it would provide needed nesting areas for Bald Eagle populations. 

On the other hand, the local infrastructure would be stressed: Where will the construction crew live? What about their families? How would the roads handle 2000 workers in a town currently populated by 900 people? What about the sewage system? The school system? Looking at the longer term, the dam would create a large lake, where once there was a river. Land that supports a wide variety of species would be lost beneath the newly-formed lake, and the transition from the cool, fast-flowing water of the river to the slower, warmer water of the lake would have a profound effect on the species of fish living there. 

Those are only a few of the pros and cons. There are many others. Read the full scenario here for more details. 

After a group discussion, each student was assigned a role to play. For example, one student might be portraying a land developer who is interested in the building and selling lakeside homes, while another might be acting as a Native American concerned about heritage sites being submerged beneath the new lake. Each student is using the situation to write a short persuasive essay about why the town should or should not vote to construct the dam, based on their character's interests. 

These issues aren't black and white, and today, we ventured out to see how they've played out in our own community. There are a number of dams along the Huron River, and we visited one of them today: 

Barton Dam, frozen solid

Some brave souls ventured the cold and the wind to take a look from the walkway above the floodgates. 

The view from the walkway on the floodgates. Sam and some of our class are visible waving to us on the right. 

Looking straight down from the walkway. There were some amazing ice structures to check out. 

 

Not everyone was complaining about the cold. 

Heading back to the warmth of the buses. 

STEM: Flow in cities and our bodies

As part of our Cities theme, we've talked a lot about the concept of flow. Electricity, water, traffic, people, resources, internet bandwidth, and phone lines are just a few of the many types of flow that are vital to a city's operation. One gauge of a city's health is how efficiently these systems operate. 

In Math today, the blue group (and our visiting fourth grade guests) took this concept and applied it to our bodies, measuring our pulse rate after sitting at rest, then again after doing twenty jumping jacks, and then a third time after quietly stretching out on the floor with our eyes closed for a few minutes. When we saw the changes in the rates after each activity, we talked about the reasons behind them: Why does your heart rate go up during physical exertion? What's happening in your body, and why? 

Warm-Up activities

We opened and closed our day with a math problem involving triangles. First, kids worked on it this morning on their own or in small groups. In time, everyone got to the correct answer. The really interesting part was later in the afternoon, when a sampling of kids took turns explaining how they had solved it. Of the kids who shared their processes, we saw at least three different methods (and a few variations) on how to approach the problem.

Wiring up Ant Arbor with Joanna's class

We had a lovely afternoon with Joanna's class today, working to install lighting circuits in the model homes built by the younger students. 

We've spent a lot of time in class (read more here, here, and here) on the topic, and today we got to apply our knowledge by showing the younger kids how to wire two LEDs using parallel circuits. 

It was a lovely opportunity for cross-classroom collaboration, and every single one of our kids did a wonderful job with their younger partners, carefully explaining the set up and teaching them how to replicate it themselves. 

Our group outnumbers Joanna's, so we also had a tiger team of specialists available to help strip wire, divvy out supplies, and help troubleshoot problems around the room. 

It was really an impressive showing by all of our kids, striking an excellent balance between demonstration and teaching as opposed to just doing it for the younger kids. They did a great job today!

STEM: Learning about circuitry and wiring

We've been learning a lot about electricity as part of our STEM work with our Cities theme. We'll be putting this new knowledge to use later this week when we visit Joanna's 3/4 class to help them install lighting in the tiny city that they're building in their classroom ("Ant Arbor"). 

Before we can teach the younger kids, we needed to get some experience ourselves: 

We disassembled switches, outlets, and power cords, examining the inner workings. 

Most kids didn't know how to strip a wire, so Marcellin shared his expertise by teaching a mini-workshop about how to use the tools to prepare wires to be connected. 

We'll be visiting the 3/4s on Wednesday afternoon to begin helping them illuminate their cities. 

STEM: Chromatography lab

We had a guest teacher yesterday afternoon! Laura Cesa visited from the University of Michigan to lead us in a chromatography lab. We used the ink in markers to get a hands-on experience with the components of solutions, making connections to the often invisible contaminants that can enter our drinking water. 

Read a little more about it here. 

Thank you for visiting, Laura! 

STEM -- Ohm's Law

For the last couple of weeks in STE/Math the middle schoolers have been learning about electric circuits.

We started with the initial prompt: "Here is a battery, a lightbulb and some wires. Make it light up."

After the initial investigation we discussed the key elements that are needed to complete a circuit: a closed path, a voltage source (battery), a load (lightbulb).

Now students were asked to investigate more complex circuits with multiple bulbs and batteries. 

In math class we were able to go a little more in depth into the relationship between the number of lightbulbs, batteries and the brightness of the light (the energy usage rate, which we came to learn in this case is directly related to the current). From some thought exercises, experimental observations (we also talked about independent and dependent variables) and a basic understanding of the mechanism of electrical current we we're able to derive an approximation of Ohm's Law for series circuits--basically doubling the voltage (number of batteries) makes the bulbs twice as bright and doubling the number of lightbulbs cuts the brightness in half.
This led us a little further into math as we talked about direct and indirect proportions; the green group even got a little into the characteristics graphs of direct (a line through the origin) and indirect proportions (a hyperbola with the axes as asymptotes).