I try not to post things with anything approaching obscene language, but sometimes, as in this piece, called “Storm” by Tim Minchin, it’s a small part in the service of a much bigger, more significant idea. Anyway, this one might not be for the kids.
Squid Dissection
To follow up my own attempts at a fish anatomy lesson, I asked the people at the Gulf Coast Research Lab’s Marine Education Center to include a dissection in their program for our Adventure Trip. They chose squid.
Squid are nice because they’re mostly soft tissue and the organs are fairly easy to identify. They’re also quite charismatic, which piqued the students’ interest. These squid were going to be used as bait, so I didn’t feel too badly about using them for science.
Once again, our guide, Stephanie, was an excellent teacher. A good time was had by all, even though it was a bit gruesome.
I would have liked to have a little more time to draw some diagrams, but I don’t think my students would have had the patience. It was the Adventure Trip after all, and they’d much rather spend the time outside.
As for the future, I like this note about squid dissection:
… this … is a tactile experience. You may want to explore this aspect through sensory activities, written descriptions, poetry, and/or artwork. Encourage students to experience the many textures found inside and outside the squid’s body. Moving fingertips along the suckers is suggested as well – the suckers do not scrape or hurt if you are gentle with them.
–Center for Educational and Training Technology, Mississippi State University: Squid Dissection
This quote comes from a Mississippi State website, which also has a great set of calamari recipes in addition to dissection instructions. I’m always in favor of an interdisciplinary approach; food-preparation rather than purely dissection.
Finally, the University of Buffalo’s Biology 200 class has some excellent, labeled pictures, for reference.
Variations on a Theme
In seeking their identity, adolescents try out a wide variety of different personas. These are often closely associated with changing appearance and style. What I find interesting is how the different styles increasingly cross cultures and other traditional divides (like race). This is evident in Ari Versluis and Ellie Uyttenbroek’s photographic series Exactitudes.
There’s something sad about the loss of local cultural uniqueness to globalization; it’s a bit similar to the feeling you get when you hear about another interesting species becoming extinct. Curiously, however, when Versluis and Uyttenbroek tile together photographs of different people from the same subculture striking identical poses, they not only highlight the similarities between very different people, but also the minute variations that individuals employs to make the subgroup’s “uniform” their own.
All 128 pictures sets are thought provoking and worth a look. I think they would make useful subjects for students to reflect on (though, warning, there is a little nudity in one of the sets).
(via Brain Pickings)
The Uses of Rare Earth Elements
Tiny quantities of dysprosium can make magnets in electric motors lighter by 90 percent, while terbium can help cut the electricity usage of lights by 80 percent.
–Lifton (2010): The Battle Over Rare Earth Metals
There has recently been a bit of a furor over the fact that, currently, China produces 90% of the world’s rare earth metals. Special properties of these elements are making them extremely important in a lot of high-tech and alternative energy technologies.
Fiber-optic cables can transmit signals over long distances because they incorporate periodically spaced lengths of erbium-doped fiber that function as laser amplifiers. Er is used in these laser repeaters, despite its high cost (~$700/kg), because it alone possesses the required optical properties.
–Haxel et al., 2005: Rare Earth Elements—Critical Resources for High Technology
The rare earths are so chemically similar that they’re lumped together in one corner of the periodic table, which is why they have not been used a lot until now. Only recently has their influence on elecromagnetic systems been discovered. Wikipedia has a good list of the elements with some of their uses.
Many people are worried about one country controlling so much of a single resource, especially since China cut its export quotas earlier this year. Fortunately, rare earth metals are found in places other than China, and, as the demand continues to outstrip supply, it’s just a matter of time for high prices to to bring more mining and recycling projects into production.
Government and Geology in Nashville
Earlier this spring, we had an excellent immersion trip to Nashville. The primary purpose was to visit the capitol and meet with Memphis’ State Representative Mark Kernell.
But we also had time to visit the Abintra Montessori School in Nashville (who returned the visit last month), and have an excellent hike along a limestone-bedded stream in Montgomery Bell State Park. The hike, however, was not without some controversy.
Shilo and Pickwick Immersion
The Shiloh National Battlefield is only a couple hours east of Memphis (or west of Nashville), and its proximity to Corinth, MS, and a state park with a hydroelectric dam, make it an excellent place for an immersion trip during the cycle when we study the U.S. Civil War and electromagnetism. Two years ago, on a couple beautiful, sunny days in the middle of spring (early April), almost on the anniversary of the battle, we made the trip.
We drove over on a Tuesday morning, and since our very nice cabins at Pickwick Landing State Park were not quite ready yet, we ate the lunch we’d brought with us at a picnic shelter on the park grounds. The choice of picnic shelter number 6 was serendipitous, because not only was it beautifully located, but just down the hill, at the edge of the water, is an excellent outcrop of fossiliferous limestone.
After unloading at the cabins, we took a short, afternoon drive to see the hydroelectric dam.
The next morning we hiked along the Confederate line of advance during the Battle of Shiloh.
It was a relatively long hike, but useful in that it allowed students a feel at least for the scale of the battle, and the conditions the soldiers endured. There was also a nice museum at the end, with an interesting video and an excellent demonstration from one of the park rangers (you need to book an appointment ahead of time).
Finally, on Thursday morning, on our way back to Memphis, we stopped at the Civil War Interpretive Center in Corinth, Mississippi. The museum is excellent, especially the Stream of American History, which is abstract enough that it makes a great puzzle for students to figure out.
The map below shows the locations of the stops, and has links to the posts about each stop.
View Shiloh Immersion in a larger map
Block Schedules
Jenny Anderson has an interesting article on a New York school that changed from the typical 45 minute class periods to longer 130 minute “blocks” (thanks to Kara D. for pointing this one out). The whole idea of set class periods is one I’m having to get used to again as I move out of my one-teacher, one-classroom middle school at Lamplighter where time management is a lot more fluid.
Apart from Spanish class (30 minute class period), everything was pretty flexible at Lamplighter. In theory, I would have a short, spark-the-imagination type lesson at the beginning of each week for math, language, and social/physical science. Then, for the rest of the week, students would use the two hour morning and afternoon blocks to do whatever individual or group work they needed to get done.
In theory at least.
In practice, my lessons would tend to last a lot longer; I like to promote discussion, and once you get them going, adolescents often find it difficult to stop talking. So, almost inevitably, a quick review of the novel chapter they read last night would devolve into a discussion of something like Mutually Assured Destruction and continue onto the potential for accelerated evolution due to nuclear fallout, and then to the parts of atoms and why some elements are radioactive and some are not.
I also found that I would have to assign specific blocks that prioritized group work. It’s hard, apparently, to arrange everyone’s schedules to do group work, even when you’re with the same group of people, in the same classroom, all day at school. Part of this though is that, in giving students so much control of their time, students find their own rhythms to the days, with, say, math in the mornings and language after noon, that may not match up well with each other. So I’d find myself saying, when we restarted after lunch, “Remember your group projects are due tomorrow, so you might want to get on that.” And, typically, they did, getting the group work done before going back to their individual work.
The key difference with a set time period for each class, is the tendency for the teacher to feel that they have to stay on subject for the entire period. There are, of course, different topics and subjects that need the full period or block, and I certainly favor having a longer time period to work with, but there are times when you might feel the urge to artificially stretch the work just to fill in the time. This problem was mentioned in the article:
Another complaint: boring 45-minute classes became boring two-hour classes. Robert Ronan, a senior, said, “There are some classes that lend themselves more easily to 2-hour-and-15-minute classes and teachers that can do that, but I sort of feel like a lot of the classes are the same, just stretched.”
–Anderson, 2011: At Elite School, Longer Classes to Go Deeper
It seems to me, that if you don’t want to lecture or have a discussion for entire two hours, which could get boring if not done really well, and you want individual or group work, which some students will complete faster than others, you are going to be faced with students who have time on their hands. You’d prefer that they spent that time productively, and definitely don’t want them distracting other students, so there need to be clear expectations about what they should be doing in these interstitial moments.
I’d lean toward making sure they know how much time they have before you need their attention again (or they have to leave) and then giving them the choice of what to do: they could start on homework for this or even another class; they could take a quiet break to relax and recuperate (journaling might be a good idea); or they could do what you’re probably doing, and go around helping their peers with the work at hand.
Within the same block of time:
Blind Sampling of the Subsurface
On the first morning of the Coastal Science Camp, between dip netting and seining at the estuary, we tried sampling beneath the seabed using a little coring device which I seem to have to forgotten the name of.
Usually, they can see the little holes in the seabed where the benthic macrofauna live, but not this time. All the sediment pouring into the Mississippi Sound from this spring’s swollen rivers had made the waters too turbid to see through. So we were coring blind.
The corer is simply a metal (stainless steel) barrel with a rubber piston inside. The piston is connected to a handle at the top with metal rod. To sample, you put the tip of the barrel at the sediment-water interface and push the barrel into the sediment at the same time holding the handle steady to keep the piston from moving into the sediment. Holding the piston steady provides a little suction on the inside of the barrel, which helps the barrel move into the sediment, and keeps the sediment in the barrel when you pull it out. However, it does help to put your hand on the bottom of the barrel as soon as possible to keep the sediment from falling out, even if that means sticking your hand into the sediment itself.
Once you’ve recovered the sediment, you extrude it into a sieve. Sometimes you can see a little layering in the extruding sediment, but we did not take the time to try to interpret it since our focus was on finding benthic fauna.
The sieve’s mesh is pretty coarse, so anything sand sized or smaller is washed out as you gently rock it back and forth in the water. We did not find much. Mostly small pebbles. Without being able to see the seabed our sampling pattern was pretty random.
The more persistent groups (the class had been broken into groups of two or three) did find a couple things, including a polychaete, which is a segmented worm.
They also turned up a small, clawed, lobster-like organism:
We also found the burrow of an unknown organism, surrounded by a clayey cast. It looked very much like some of the fossilized burrow casts we saw at Coon Creek.
This type of sampling was not everyone’s cup of tea, however. Fortunately, the water was shallow and warm, so a good time was had by all.
