Category: Year 8 Science

Year 8 Energy Project

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Welcome back to Term4 and the start of Spring! This term we will be working with students in Tasmania, New York and Lima on our Energy projects. As revision of some of the work we did last term, please complete this short quiz at BBC Bitesize KS3: Science: Energy transfer and Storage. Take a screen shot of the test result and email to me at my gmail address.  Then go to the Energy Challenge Wiki and start your research. Your goal is to work in a team to produce a 20 minute presentation to teach other students about a specific type of renewable or non-renewable energy resource.

Over the holidays we had a visit from AGL, who replaced all our incandescent globes with energy-efficient globes. For each 10 globes replaced, 6 renewable energy certificates are issued, which is equivalent to 6 tonnes of  carbon dioxide. These certificates are part of the Australian Governments Renewable Energy Target. We also recieved information about the Willatook Wind Farm proposed by Wind Prospect, which joins the Macarthur and Penshurst Wind Farms as significant, renewable energy projects in our region. Hotrocks Ltd have also been doing geothermal investigation in the local area.

At present, most of Victoria’s electrcity is produced from brown coal in the LaTrobe Valley. Much of this power is used in manufacturing, especially by Portland’s Alcoa Aluminium smelter. Find out how much of Victoria’s power is used by Portland Aluminium. Why do you think the Moyne Shire has become an area of interest for wind and geothermal energy and not hydroelectric and solar energy? Please post your answers in the comment section below.

As part of our Energy studies we will be looking at Geothermal Energy, which involves some geology. Go to this Google Doc “The Plates of the Earth”, save the document onto your netbook and complete the tasks and questions. Then email your completed work to me at my gmail address.

Dark and stormy night

making_a_torchYear 8 students have just begun a unit of work on electricity, by making a circuit and a switch from simple materials, such as aluminium foil, drawing pins and paper clips. Their next task is to make a torch that can be operated with one hand. Imagine you are driving with Dad in the car on a dark and stormy night. The car breaks down and Dad has to walk to the nearest house, about an hour away. You scratch through the glove-box and behind the car seat and this is what you find:

  • 2 batteries
  • cardboard tube
  • aluminium foil
  • paper clips
  • drawing pins
  • sticky tape
  • copper wires
  • a globe from the overhead light

Can you make a torch, with a switch, that can be turned on and off with one hand? Your torch will be judged on it’s reliability, ease of operation, brightness of beam and sturdiness of the connections.

Two International Science Projects

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The International Paper Airplane Challenge

To finish off term 3, year 6/7 students will be learning about the scientific method, while they research, make and fly paper planes. Students from three  other schools, in Philadelphia, New York and Tasmania, will be doing the same experiments and we will compare our results. Ms Catherine Laguna from Philadelphia, Dr Gerald Ardito, from PVC Middle School (NY) and Mr Deon Scanlon from St Aloysius Catholic College (Tas.) all teach 12-13 year old students science.

Students decide what defines the “best” paper plane for them – is it the one that flies the furtherest, most accurately, highest in the air or looks the best? They research different styles of planes and develop a hypothesis – a statement about a measurable factor of the plane (length, width, angle of wings, mass etc) that impacts on the best performance. They then write up the procedure accurately, so the experiment can be repeated anywhere, anytime, with the same results. Students choose three planes to trial and collect the data to graph and compare with international students.  Students will use The International Paper Airplane Challenge wiki to document their progress and post their videos and Google Docs to compare their results.

International Energy Challenge

This project, for year 6/7 and 8 students, will involve Terri Johnson (Bode Middle School, St, Joseph, Missouri) and Kristy Lathrop (Messa Middle School, Castle Rock, Colorado) and Gerardo Lazaro (Lima, Peru)  in a Siemens – STEM – Institute facilitated collaboration. We will use the Energy Challenge wiki, Google docs, Skype and other tools to allow communication with students across the Pacific Ocean.

Terri and Kristy have already done some great brainstorming and planning during their school holidays, with the ideal aim of the collaboration being that students will:

  • see different viewpoints
  • be able to suspend judgment
  • be able to make informed decisions
  • be risk takers
  • understand that “energy cannot be created or destroyed…” and that
  • there are costs/benefits to all technology decisions

Constellations and Forces Stories

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Image Source – Creative Commons

The path followed by the Sun is called the ecliptic, and any constellation within the ecliptic is called a “zodiac constellation”. You may be familiar with these as the symbol of your ‘star sign’ or horoscope identity. The word “zodiac” comes from Greek, meaning “circle of animals” and each of the twelve (except Libra, the scales) is represented by an animal. Year 8 Science students are required to search for an image of their zodiac sign and recreate the constellation using black paper and pin-holes. Use my Delicious links at right to start. If you have completed this task, you can search for your 2010 horoscope, and we will try to guess which prediction is true for each student in the class.

What is the difference between astrology and astronomy?

Have astrologers contributed to the science of astronomy?

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Year 6/7 students will be creating a children’s story book to teach Mrs. Lee’s prep/1 class about Forces. You will use the on-line program “StoryJumper”, which allows you to add scenes, props, text and a cover to an on-line story book. Make sure your story includes one or more of the following forces: Gravity, Bouyancy, Friction, Surface tension, Magnetic forces, Muscular Forces, Static Electricity or Lift. Here are some examples of stories I have written and illustrated to demonstrate:

“Gravity and the Baby Bird” by Britt Gow

“Platypus Forces” by Britt Gow

You will need to sign up to “StoryJumper” and activate your account using your school email address. You can access your school email account at any time by going to webmail – make sure you have this link book-marked, so you can get to your email quickly and easily.

Year 8: Simple Machines

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This week in year 8 Science we are starting a unit of work on simple machines, which includes inclined planes, wedges, screws, levers, pulleys, wheels and axels. I have saved some links to good sites in Delicious. The first task for students is to create a mind map (use Inspiration, Freemind or Bubbl.us) to show the six different types of simple machines with at least one pictorial example of each. You could also try the Google Labs app “Squared”, which produces a table of information including the type of simple machine, an image and a description.

The purpose of a machine is to reduce the effort required to do work – this is achieved by increasing the speed or increasing the distance,  while reducing the force required. This concept is represented in the equation W = F x D (Work = Force x Distance). Before the invention of the steam and combustion engines, much work was achieved using simple machines and human or animal labour. In the picture above, a wooden block from a sailing ship, a pulley is a wheel and axle used to change the direction and decrease the effort required to lift a weight. Another example is the ‘shaduf’, an ancient Egyptian machine (lever) used for moving water from the river up to the bank, shown below.shaduf

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  1. Create a quiz (using “MyStudiyo” or Powerpoint) about simple machines, with at least ten questions.
  2. Create a poster with a compound machine (eg. A push-bike, excavator, front-end loader etc) and label each component machine. Make sure you include information about how your machine works. “How Stuff Works” is a great site to help you with this.
  3. Create a photostory explaining about each simple machine or how a compound machine works. Make sure the images you use are copyright free – use Flickr (Advanced Search – Creative Commons) or Google Image Search (Advanced – Free to reuse)
  4. Invent a machine and create an advertising brochure about what it does and how it works.
  5. Do this webquest about simple machines which includes creating a table, a model and a poster.
  6. Edheads has a great site for learning more about simple and compound machines.

Simple-Machines-Rachel

Congratulations Rachel on this outstanding example of a Bubbl.us mind map about Simple machines. Well done!

Food Testing in Year 8 Science

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A balanced diet includes fresh foods in the correct proportions of carbohydrates, proteins, fats, vitamins, minerals, fibre and water. This week in Year 8 Science we will be doing food testing to find out which foods contain carbohydrates (sugars and starch), protein and lipids (fats and oils).

Benedict’s Test – a test for sugars. Benedict’s reagent  is a solution of copper sulfate, sodium hydroxide and tartaric acid. When heated with a mixture of the food it turns from blue to yellow, orange or brick-red.

Iodine – a test for starch. Break the food up into small particles with a mortar and pestle and add a few drops of iodine. If starch is present, the mixture will turn dark blue. Virtual starch test here.

Buiret Test – for protein. Sodium hydroxide and copper sulfate are added to an emulsion of the food. If peptide bonds are present, as in proteins, the mixture will turn from blue to violet/purple. Virtual test here.

Brown paper or Emulsion test – for fats and oils. Rub a small amount of the food onto brown paper – if it appears transluscent, lipids are present.

Year 8 Science: Human Body

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Year 8 Science students will continue their study of the human body with an exploration of the digestive system and nutrition. This will include food testing for glucose, starch, lipids and proteins. We will also use the National Geographic’s “Incredible Human Machine“; “Explore the Human Body“, BBC’s “Interactive Human Body” to identify the structure and function of various organs within the respiratory, circulatory and digestive systems.

Each student should keep a food and exercise diary to record the quantity and type of each food consumed over the week, as well as the physical processes that require energy each day. We will use this information to study tyour kilojoule inputs and outputs over a week – do you consume more chemical energy than you expend?

Year 8 Science – Heart Dissection

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Year 8 students had been looking forward to “D-day” (Dissection day) for several weeks. Finally, we were able to defrost the sheep’s hearts, obtained from Midfield meats, and examine their structure. Three students opted not to take part, and one was a little queasy, but we also had some budding surgeons who showed their skill with the scalpel! Students are shown here washing their hands after a successful science experiment.

Previously we have looked at the components of the circulatory system and their processes, as well as the structures and functions of the respiratory and excretory systems and will move on to the digestive system next week. In the meantime, you can watch our TeacherTube video of the Heart Dissection.

Year 8 students are asked to leave a comment here about what you learnt from dissecting a sheep’s heart and what you have enjoyed about science this semester. I will be considering these comments as I write your reports, so write your comments in full (no text talk) and be thoughtful.

The Carbon Cycle

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This week in Year 8 Science we will be doing some work on the Carbon Cycle – as a bridge between the studies of chemistry and biology. Make sure you understand the following terms:

Respiration (glucose and oxygen react to form carbon dioxide and water)

Photosynthesis (carbon dioxide and water react in the presence of sunlight and chlorophyl to form glucose and oxygen)

Decomposition (Living organisms, such as bacteria and fungi, break down organic matter)

Fossil Fuels (Hydrocarbons – gas, oil and coal – formed over millions of years from once-living organisms)

Combustion (Burning of biomass or fossil fuels, which produces carbon dioxide and water)

Biomass (the mass of living organisms – plants, animals, fungi, bacteria and protists)

Calcium Carbonate (chalk, which eventually forms marble, from the long-dead remains of molluscs and other shelled sea creatures)

After watching the DVD “Crude”, you are required to produce a story book using “Comic Life” , “Kerpoof” or “Storybird” with the title “My Life as a Carbon Atom”, demonstrating your understanding of the above processes. You could get some ideas here, or this YouTube video. Start with a cartoon storyboard or write a rough draft and then ask me to check for accuracy before you create your masterpiece! This piece of assessment is dueby close of business on FridayMay20th.

More information about the educational uses of Comic Life here.

Biodiversity – CSIRO Program

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On Tuesday we had a visit from Elke at the CSIRO. Her program was all about Biodiversity – the great variety of living things on earth, how they are classified and why some are threatened with extinction. This image shows one of our students using a dichotomous key to identify Simpson’s characters. Other activities included laser monitoring of landscape temperature, temperature in a carbon-dioxide enhanced atmosphere, pH testing of water, soil texture, soil moisture and microscopic monitoring of species.

In Year 6/7 Science we will be learning about the characteristics of living organisms and the classification of animals. I have used Bubbl.us to create a dichotomous key as an example for students. They will use the same tool to create their own key to identify items of their choice – for example flavours of icecream or drinks, different balls or sporting equipment. Here is an example of a key to identify Fungi.