Friday, January 13, 2017

Electricity, Food Webs, and GMOs

Electricity:
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.

GMOs
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.








































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