Friday, January 13, 2017

Electricity, Food Webs, and GMOs

In recent weeks the 3rd and 4th grade students have been studying electricity. We began by exploring how electrons behave, both as static electricity and in the form of a current, and have enjoyed using a Van de Graaff generator to make pie plates fly, hair stand on end, and to (gently) shock ourselves and our friends!  We then began experimenting with simple electrical circuits.  I challenged the students to construct a simple burglar alarm that would turn on when a cabinet door was opened, using a battery, wire, a buzzer, and aluminum foil. This was particularly challenging, because it requires figuring out a way to make the circuit be on when the cabinet door was opened. This is more difficult than designing a system where the opening of the door breaks the circuit. Nonetheless, nearly early every team figured out a way to make their alarms functional, and in the process developed a greater understanding of what electricity is, how it behaves, and how it can be used. 

Food Webs:
In fifth and sixth grades the students have been developing their own unique card games based on their study of an Earth biome, modeled after the game Into the Forest.  This game is designed to help the students understand the intricate connections between all of the living things in a food web, and the relative importance of each type of plant and animal in a functioning ecosystem.  They are researching and building 7 different versions of the game, for biomes, such as the Great Barrier Reef, the Russian Taiga, and the Chilean Rainforest. They have to choose animals and plants from their chosen ecosystem and understand how every organism relates to every other as predators and prey, producers, consumers and decomposers.  Every organism is assigned "energy points" based on their role. This has been a nice integration with Math, as they have been calculating the "# of things it eats"/"# of things it gets eaten by" ratio for each animal as a strategy for determining their position in the food web, and thus how many energy points they should have. Ultimately, it is the students who must choose a standard "rule" that helps them to assign these points in a way that makes sense from a biological perspective, but also allows for effective game play. They are creating illustrations of each organism for the actual game cards, and we can't wait to try them out!  They are working now to create professional versions of their games using an online printing service, and once finished, each student will receive a copy of the game to take home and play with their families.

Recently the 7th and 8th graders have been investigating the emerging prevalence of genetically modified organisms (GMOs) is our society, the positive and negative impacts that they might have, and the controversy surrounding them.  In homeroom the students have read several articles about real life GMOs that have recently been approved for use in the United States (salmon and mosquitoes), and have self reported words that they are unfamiliar with in the articles. Then in science class, they were given an assignment to propose their own GMO, to identify the problem they you are trying to solve and to paraphrase how the GMO solves that problem, to describe how the genome of their organism would be changed. They were then asked to give their animal or plant a commercial name, to anticipate the ways your organism may be criticized, and to list the safety precautions that they would take to make sure their GMO is safe. The students then presented their ideas to their classmates, who were then asked to compare the benefits and risks of the GMO, and to criticize or defend its production. This assignment inevitably brings up practical questions about the actual genetic manipulations that are actually possible at this point in time that I am using to inform our future discussions about nuts and bolts genetics.

Our oldest students have also been learning how to make a scientific argument from evidence. By exploring the parts of a good argument, they are discovering how to evaluate the sometimes baffling amount and type of information that they may encounter on the internet about scientific topics. Specifically, they have been working through an exercise that explores arguments that can be made for the possible causes of global warming.

Friday, November 18, 2016

Weather, Climate, and Data Collection

This fall in science at Summers-Knoll, the 7th and 8th graders have been focusing on Weather and Climate change.  They are learning what natural force determines the weather (the uneven heating of the earth by the sun), and how the resulting movement of air and water develops into wind and precipitation.  We have just purchased and set up a weather station so that students can ultimately make daily observations and starting making their own forecasts. Our station is part of a network of citizen weather stations at wunderground.  You can take a look at it here:
 At this grade level, the students are engaged with a number of hands-on activities, but are also expected to carry those experiences into further work in homeroom as well.  For example, during science time the students created a “cloud in a bottle”, which involves two related single variable experiments and introduce the concepts of  humidity, temperature, condensation and condensation nuclei as necessary for cloud formation.  Then, as a follow-up in home room, they are writing paragraphs to communicate the relationship between what they saw in the lab and real life weather in the world.  In another activity, the students used ice cubes colored with blue food coloring and warm water stained red to create a model that visually demonstrates how air masses move in our atmosphere in three dimensions.  We have been studying how these warm and cold “fronts” can cause flooding, like the kind that has caused evacuations in Iowa earlier this fall, and like we saw locally in Ann Arbor several days later. The class then travelled to the Broad Museum in Lansing Michigan, to visit an exhibit of photographic and video work by Gideon Mendel called Drowning World.
Drowning World is a visual attempt to capture the magnitude of climate change through portraits of flood survivors taken in deep floodwaters, within the remains of their homes, or in submerged landscapes, in the stillness of once lively environments. They invite the viewers to reflect on our impact on nature and ultimately, on our own attachment to our homes and personal belongings. See Karl’s blog for further information about their trip and to see photos.
    With an eye towards making future forecasts of their own, the 7th and 8th graders have been learning how high and low pressure systems across the planet drive the direction of wind and precipitation all over the globe, which is key to developing the ability to predict the weather.  We are also using this topic to strengthen our note taking skills, and to learn how to record ideas that are new to us in a way that we can decipher later, an ability that is necessary in all disciplines, not just science.  They then used their notes to answer questions about the movement of wind around some fictional low and high pressure systems.  
 As part of a longer term project, the students have also constructed homemade barometers.  We use this project as a vehicle for learning how to design data collection tables in a way that makes it simpler to analyze our data in the long run, and the students have learned how different data collection formats can either assist or impede our ability to analyze our information quickly, depending on the question we are trying to ask. It also introduces the students to the art of “trouble-shooting” equipment and experiments, which is a necessity that every scientist understands.
Students at this grade level are also asked to begin to accumulate and use a larger scientific vocabulary, that the students quickly learn they need to understand in order to have meaningful discussions about the work that they are doing.  We periodically work on crossword puzzles of important vocabulary words, and students that are comfortable with their answers come to the whiteboard to demonstrate their knowledge to others in the class. This also gives those who are less confident another opportunity to learn and ask questions.

Citizen Scientists and the Monarch Butterfly

In 5th and 6th grade this fall, we have been studying monarch butterfly caterpillars, some of which were happily discovered in the milkweed garden that the 5/6 class planted last spring. The students used anatomical markers to determine the molting stage, or “instar”, of their caterpillar, and to track its development.  This is a great way for kids to learn how to keep a daily log of observations and measurements.  The students then use the data they collected from their Monarch caterpillars to generate line graphs that visually communicate their results.  They are also learning how their qualitative observations, such as “the caterpillar molted last night”, or “he ate a ton today!”, can actually help them to explain mysterious changes in the caterpillar’s rate of growth that they discover from their line graphs. Being able to communicate scientific results is an important skill that we practice at all grade levels.
  When their caterpillars pupate and emerge as butterflies, the students tag them with an identifying number as part of a program to track migrating monarchs at the University of Kansas called Monarch Watch.  They then release them, sending them off with a hearty “Adios Mariposas!”, to help carry them to their ultimate destination in Michoacán Mexico where they stay for the duration of the North American winter.  The kids continue to track the butterfly migration and to record their sightings at Journey North.  The 6th graders had an opportunity to tutor the 5th graders in how to navigate the Journey North website, and everyone opened their own accounts so that they can record sightings of the migrating butterflies they observed “on the wing” in Michigan.  We had a great discussion about what a good “scientific” report should contain, and the students wrote practice reports and discussed what elements of their reports had scientific value.  For example, when they report a butterfly sighting, details like the weather conditions, the prevailing wind direction and speed, or the presence or absence of nectar plants can be useful for the study.  In contrast, information about how they felt at the time, or what they had for lunch, or who they were with, are “superfluous” pieces of information that are wonderful for a personal journal or narrative, but not so for scientific observations.  In preparation for the return of the monarchs in the spring, we have planted milkweed in our permanent raised beds, and are working on the construction of a “Monarch Waystation” here at Summers-Knoll.

Thursday, November 17, 2016

The Nature of Light (3rd and 4th Graders)

This term the 3rd and 4th graders have been continuing with exploratory experiments that are meant to help them understand the nature and behavior of light. In one activity, the students attempted to sort Skittles by color using white light, or single colors of red, blue, or green. ( Ask your student what happens when you are limited to one illuminating color). This exercise helped to demonstrate how color is perceived by our eyes and our minds.
We delved deeper into our understanding of light, color, and perception, with another activity studying colored shadows.  We observed that shadows are usually black, but that color shadows can be generated when multiple colored light sources are used.  The students systematically observed the results of subtracting different light sources, and did a wonderful job of deducing why the shadows changed color or changed position, based on what they already understand about light.  (Ask your student what they observed). In honor of Halloween, we made our own ghosts using reflection. This method, called "Pepper's Ghost", is the same method used by Disney to project the ghosts in the Haunted House! As we finish up our investigation of light, we have been comparing what we know about how light behaves as a wave with the behavior of light that makes it seem like a particle.  The students observed the angles of reflection that light follows when it bounces off of a mirror, and compared that with a super-ball bouncing off of the floor.  Soon we will be changing gears and begin studying electricity.  Ultimately, we plan to merge our themes of light and electricity and construct our own lightbulbs.  Stay tuned!