One of the major themes that runs through many facets of science is the notion of surface area to volume ratio. I remember being a Peace Corps Volunteer in Kenya and using an experimental, guided-inquiry curriculum, inspired by the British Nuffield science program. Students made plasticine cubes of various sizes. I’m not sure why British people have an aversion to clay, but plasticine seems to be their school sculpting material. Then students measured the surface area of the cubes and calculated the volume. Then they calculated the surface area to volume ratio and discover that the larger the object, the smaller the surface area to volume ratio.
Which helps to explain many types of adaptations in biology and why individual cells can’t be the size of houses; they would simply not have enough surface area to absorb the materials they need, like oxygen, or to expel waste. From villi in the intestines to convolutions in the brain, our bodies have many adaptations to increase surface area.
Adaptive Curriculum has a guided inquiry Activity Object called “Surface Area to Volume Ratio in Organisms.” A clever engagement draws the students into the interactive experience. You have a plate of cheese with different size cubes that you are going to put into the microwave. But first, learners predict whether the large cubes or the small cubes will melt first.
Obviously, the small cheese cubes will melt before the larger ones. If you thought this, you have experienced a discrepant event. In actuality, the large cubes melt first. Since the microwave heats from the inside, the smaller cubes lose their heat faster than the large ones. The larger cubes, thus retain more heat and melt faster. Discrepant events are powerful, because learners want to know why they were wrong.
From this, learners virtually change the size of cubes and see the changes in surface area, volume, and surface area to volume ratio. Then body sizes and shapes of animals are explored, as students learn about the implications of size and shape for heat loss.
My Peace Corps teaching and Adaptive Curriculum are different modes of guided inquiry and discovery learning, but both can help produce deep and life long learning.
Back in 1985 I was fortunate enough to visit George Awad’s New York studio where he was using his architectural skills and space interests to construct a scale model of the universe. Awad used one million of his own dollars to make this and it was very impressive and enlightening.
This is how Carl Sagan (1997) described it in his book THE DEMON-HAUNTED WORLD: Science as a Candle in the Dark:
Perhaps the grandest museum exhibit can’t be seen. It has no home: George Awad is one of the leading architectural model makers in America, specializing in skyscrapers. He is also a dedicated student of astronomy who has made a spectacular model of the Universe. Starting with a prosaic scene on Earth, and following a scheme proposed by the designers Charles and Ray Eames, he goes progressively by factors of ten to show us the whole Earth, the Solar System, the Milky Way and the Universe. Every astronomical body is meticulously detailed. You can lose yourself in them. It’s one of the best tools I know of to explain the scale and nature of the Universe to children. Isaac Asimov described it as ‘the most imaginative representation of the universe that I have ever seen, or could have conceived of. I could have wandered through it for hours, seeing something new at every turn that I hadn’t observed before.’ Versions of it ought to be available throughout the country – for stirring the imagination, for inspiration and for teaching. But instead, Mr Awad cannot give this exhibit to any major science museum in the country. No one is willing to devote to it the floor space needed. As I write, it still sits forlornly, crated in storage.
In my office, I have the model of the Big Dipper that George Awad gave me during that 1985 visit. After seeing so many 2-dimensional drawings of the big dipper, the model is a 3-dimensional view that shows how relative size and distance influence what we see in the night sky.
Then there was the famous Powers of Ten Video (or applet) that gave us the broad view of the universe and kept on magnifying by ten, until we arrived in Florida, and then descended into a plant.
Now the folks at Primax Studio have done their own Scale of the Universe with drawn images, instead of partially using photographs, but the music and the interactive aspects make it delightful to explore.
The scale of the universe is difficult to fully appreciate but we are getting closer due to multimedia tools. A 3-d Imax movie will soon be in theaters.
The videos on television show some of the massive destruction and the human toll of the recent earthquake in Haiti. It is difficult to imagine the suffering of the Haitian people. It is an unfortunate example of the devastation of a magnitude 7 earthquake.
It is natural to wonder why or how. When students are ready, teachers may want to discuss earthquakes and their causes.
The folks at IRIS have a website with a PowerPoint presentation and Quicktime movie that explain a lot of details associated with this particular earthquake and earthquakes in general. The PowerPoint has excellent pictures of the destruction to buildings, without presenting images of human suffering that would be difficult for some students. The image to the right is taken from the PowerPoint.
IRIS (AKA the Incorporated Research Institutes for Seismology) has lots of resources for learning about earthquakes including SeisMac 2.0 which allows Macintosh computers to become seismographs.
In the quest for Science Literacy, we strive to give students an understanding of natural events before they happen. Adaptive Curriculum has two strong Activity Objects, one is on determining the magnitude of an earthquake and the other is determining the location of the earthquake. The image below is from “Earthquakes: Measuring Magnitude.“
I had the good fortune last week of being a conference presider for Irfan Kula, a talented educational designer. His session was “I Love Symbiosis.” He emailed me his PowerPoint presentation, and I am presenting this here: i-love-symbiosis-kula.
I am at the NYSCATE Metro Conference, in Rye, NY. I grew up about 45 minutes from here but I forgot that it is still cold in mid-May. But of course, everything is relative, and relative to Arizona almost everywhere else is cooler.
This activity series on weather is presented by PBS, and it has a great feature–you can add the activities directly to your school web site. I present the activities and what this would look like on your website below.
Resources:
Adaptive Curriculum’s “Hurricane Formation” (which allows students to learn that humidity, water temperature, and wind speed are important factors in hurricane development).
The Texas Computers in Education Association conference just ended and I am on the plane heading home. It is a nice conference, with lots of exhibitors, presenters, and attendees. I am going to infer that Texas loves science, because at my presentation, which had a narrow niche of middle school science, critical thinking, and state standards, I estimate there were 300+ people.I posted the PowerPoint for this presentation on the last blog.
I thank District Administration’s Kurt Dyrliand Scholastic Administrator’s Ken Royal, who did one of the first articles about Adaptive Curriculum after interviewing me about two years ago at FETC. Ken really enjoyed the Activity Object on Francisco Redi, who helped disprove the idea of spontaneous generation. When Ken was a former science teacher he did this science experiment in class, replete with decaying meat and putrid smells.
It will be interesting to see if the idea of video blogging takes off. I suspect that it will do well as a medium, as long as it has either more attractive or loquacious people than me!
I have the good fortune to be in beautiful Austin, Texas today for the Texas Computer Education Association’s (TCEA) annual convention. Austin is a delightful city, and this conference is huge. In a couple of hours I am going to be doing my presentation “Critical Thinking and TEKS Science Content Via Online Activities.”
I am placing the PowerPoint file here for participants and anyone else interested in this topic. Below are some titles and resources from the presentation.
demonstrate basic relationships between force and motion using simple machines including pulleys and levers (TEKS: 7.6)
http://2dboy.com/games.php
Creature Creator
prelude to Spore
Free trial edition
How can students making creatures
Develop science content?
Develop critical thinking?
Or both?
Adaptive Curriculum Activity Objects
Dancing with the Bees
TEKS 6.12: responses to external stimuli
Determining Planet Layers from Seismic Waves
TEKS 6.6 identify forces that shape features of the Earth; 7.2: organize, analyze, make inferences, and predict trends from direct and indirect evidence
Groundwater
TEKS 6.1: make wise choices in the use and conservation of resources; 6.14 groundwater
If you want good insights and data about why lectures are a lousy tool for learning, what the fundamental flaws in school systems are, and why students are not engaged Chalkbored(by Jeremy Scheider 2007, a former high school chemistry teacher) is a must read.
Schneider makes the point that all popular movies depict US secondary schools as weak or downright bad. While there are some good teachers that rise up, they do it against the bleakest of conditions (such as in Freedom Writers).
Savvy enough to avoid the “L” word (or lecture), teachers and administrators call them discussions. In Chapter 1, Scheider writes: “In a one-hour class, a teacher who speaks 87% of the time leaves eight minutes for students. If you divide this by thirty students, each student gets to speak for 16 seconds (and listen for 59 minutes and 44 seconds). If I had a conversation like that (it sounds like a really bad blind date), “discussion” would not be the first term to pop into my head—“lecture” or “nightmare” would be closer.”
Scheider weaves great factual information with lively narrative. He makes the point often that it isn’t the teachers’ fault; it is the system that pushes them into this mode. I agreed with many of his points because they are logical and data based.
Here are some points and questions he raises. See if you agree or disagree:
If we want students to take high school math and science classes, why do we punish them by making these classes have the lowest average grades? (Example science course average = 2.68, while Physical Education is 3.34)
“Grades should never be used unless followed by clear explanations and opportunities to correct mistakes.”
The focus on Shakespearean literature and classic literature in schools has more to do with avoiding paying royalties to current authors than it does with truly trying to excite students about reading.
“Parents who want their children to succeed must insist upon higher standards than those set by the school.”
“Students should be given as much choice as we can cram into schools.”
It would be more efficient and produce more memorable learning experiences if great lessons were prepared in one place with a big budget and distributed to teachers using various media, rather than asking individual teachers to make their own great lessons.
“All meta-analyses agree that computers are more effective than traditional instruction.”
“There is no more CAI [computer assisted instruction] in high schools today than there was forty year ago.”
The book is certainly an interesting and provocative read. But if you are a classroom teacher, you probably should read this during the summer, when you can develop plans to do things a bit differently. But if you are an administrator, you might want to get a copy immediately. Scheider doesn’t just suggest change; he is trying to instill an uprising.
Living just north of Phoenix, we get the warm sunny 70° January weather, but we can drive 100 miles to the north to play in snow. Snow takes on a reverent beauty when you are just visiting it, playing in it, and having the air full of thick, downy flakes. When it makes unwanted intrusions, such as when I lived in New York, Ohio, and Iceland, it becomes more difficult to appreciate.
To the right you will see some snow fun pictures from our snow play in Flagstaff yesterday. It is interesting to see the evolution of “sledding”. Even in my childhood, toboggans were on their way out. Wooden sleds with two rails and a steering bar, like the Flexible Flyer, ruled the hills. I didn’t even see one of these on the hills.The disc or flying saucer seems to be waning.The flexible-foam, body length “sled” is the new king of the slopes. But what slides down the snow best?
The “coefficient of friction” (COF) is used to express the amount of friction between surfaces and this is proportional to the force pushing the surfaces together, or the weight of the rider and sled on the snow. The greater the COF the more friction there is. The COF for not-yet moving surfaces (static friction) is greater than sliding surfaces (kinetic friction). Engineers have measured different COFs (link). For instance, the kinetic COF for leather on oak is 0.52 and for those interested in glass-on-glass action, the kinetic COF is 0.4. Google has enlightened me. I had no idea there was so much research done on snow, and that there is a vibrant field called “snow engineering”, which might be called the ultimate snow job. Without going too deep into it, the COF for a moving skier (ski on snow) was analyzed to be between 0.01 and 0.3. I’d have to think that metal on snow would be a lower COF than foam on snow. It is good to think about, and students could do some fun experiments to find out.
Virtual science experiences must engage students and must have rich interactions. If it is just a Flash animation, I am not ready to call it an “experience” when the term video is much more suitable. If a teacher is going to bring laptop carts into a room or sign up weeks ahead for the computer lab, they should have computer-learning experiences that feature an engagement, a significant interaction, a closure, and multiple means of assessment.
“Sliding on Different Surfaces,” an Activity Object by Adaptive Curriculum, features these aforementioned characteristics. For an engagement, students play a game where they steer a sled down a hill while encountering different types of surfaces. If they steer over the surfaces with the least amount of friction, they will go faster. They receive a score based upon how well they did.
In the student interaction, students are in an office. They slide a pencil case across a desk and then mark the distance. Their mission is to find different things in the room such as a towel, newspaper, and sandpaper (obviously a rough office) and see how the pencil case sliding distance varies. (Elearning Physics Preview)
This elearning physics experience moves forward to an explanation of friction and factors that influence friction. There is an optional paper-and-pencil activity sheet that students can complete as they do the Activity Object, with two questions to be answered when they are finished.The activity sheets promote writing and become a permanent record of their learning for their science notebooks. If a teacher has a projector or interactive whiteboard and is doing a whole class lesson, the activity sheet is even more essential.
After the closure, students move onto the multiple-choice assessment, where they answer five questions and receive instant feedback about their learning. Teachers can log in to access student scores for the assessment. They can also see how long students took doing the Activity Object.If students are up for a bit of gaming, with their new understanding of friction, they can go back to the game and improve their time.
I did the Activity Object and played the game, and I observed that compared to my 8 and 11 year old sons, my sled in Flagstaff went much farther than their sleds. I would like to think that this was because I selected the patches of snow with the least friction and thus I picked up more speed. But these foam “sleds” are not very steerable and so, unfortunately, I have to consider the competing hypothesis that since my mass is a wee bit more than my sons (well okay, actually my weight is about 50 pounds more than both of them together), this may have had an influence. Since momentum is equal to mass x velocity, my momentum should be much greater than my sons’, and thus it would take longer to bring me to a stop. An impulse (force x time) can change the momentum of an object. Since my momentum is much bigger, and assuming that friction is about the same, I coast longer and thus farther.
But I think I will choose the happier hypothesis – that my greater knowledge of friction, rather than greater weight, made me go farther. Which just goes to show the subjective side of science after a happy family day in the snow.
From this, learners virtually change the size of cubes and see the changes in surface area, volume, and surface area to volume ratio. Then body sizes and shapes of animals are explored, as students learn about the implications of size and shape for heat loss.
Living just north of Phoenix, we get the warm sunny 70° January weather, but we can drive 100 miles to the north to play in snow. Snow takes on a reverent beauty when you are just visiting it, playing in it, and having the air full of thick, downy flakes. When it makes unwanted intrusions, such as when I lived in New York, Ohio, and Iceland, it becomes more difficult to appreciate.
tion, rather than greater weight, made me go farther. Which just goes to show the subjective side of science after a happy family day in the snow. 
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