Tina Bryn                                                                 LabLearner Teacher

With school back in session and flu season fast approaching, many of us teachers find ourselves asking the same question.  ‘What are we going to do to catch children up who miss labs and discussions?’

The answer to this ‘simple’ question is not so easy.  We need to look at some different variables. When having to schedule lab times it is difficult to have a student make-up a lab.  Here is one way that I used to catch a student up; I had the student who missed time just discuss with his/her group and ask what happened.  I found this strategy to be ineffective.  What ended up happening is the group members would just let the student copy his/her student data record. Instead of relying on their group members I would have the student just get the data information and then make sure they were present for the post lab discussions. This doesn’t seem to affect the auditory learners, but in some cases the kinesthetic and visual learners will need the lab to associate and put all the pieces of the puzzle together.

Another approach that I have tried this year is to have the student watch the video of the lab process, give him/her data, and discuss what they would have observed in the lab.  They will get the rest of the concepts when we discuss the questions in the post lab and focus questions the following days.  If a student misses multiple days I will meet with the student individually before, after, or during school.  I follow this same process as I mentioned above.  My only concern is that the student is not able to acquire the hands on experience and see the results of the investigations or get rephrasing in the class discussions.  The only down fall I have noticed is that when missing multiple labs, the student doesn’t perform as well on the post-test.

Knowing our students as well as we do, we will be able to decide which ones will need the hands on part for some of the labs.  With this in mind I have meet with some students before or afterschool and we will do the lab together.  I will have as much set up before hand as possible.  Obviously this takes extra time on the part of the teacher and in most cases time doesn’t allow for this.

As a teacher, I also look at the student’s strengths and weaknesses to best fit their needs of understanding concepts.  I have found that if a student only misses a day or two, it is easy to catch the student up since discussion is on the same concepts for a month.  However, this year I am finding students missing weeks at a time, and this is why I am trying the video and discussion method.  The hard part about this is that the lower elementary doesn’t have videos available.

Lower elementary teachers seem to be approaching this idea from different angles.  Some of the teachers have waited to do the lab day until all of the students are present.  This is easier for the lower elementary since teachers do not need to do a lab every week to complete the curriculum before the end of the school year.  Other teachers have chosen to go ahead with the lab making sure that the student is in attendance during the post lab, or had a peer explain what they observed during the lab.  This seems to work with the lower elementary.  Not only does the missing child get caught up with what happened, but the student getting to do the explanation is reviewing the concepts in his/her own words without even realizing it.

One teacher that I have visited with has even sent home labs to be done with the parents.  With us being a small rural school we get to know our families well.  She doesn’t send home the missed lab with all students, but she will send it home with parents that she’s knows will do the lab and return the materials.  She has done this twice in the last two years with good results.  One was the Exploring Electricity investigation 3 and the other one was the Property of Matter investigation 4.  Both times she gathered the needed materials and using one of the experiment only containers, sent everything home.  She found this way to be beneficial.  The student didn’t miss the lab and she wasn’t trying to find the time to fill the student in on what was missed.  Understand that this won’t work with all families.  She doesn’t do this will all labs or all parents; just easy to do labs and to parents that are involved and will complete it.  The student is then able to become involved with the post-lab discussions and not just have to sit back and listen.

Tina Bryn – I teach for the Barnes County North School District at the North Central campus near Rogers, North Dakota.  We are a K-12 school with an enrollment of about 155 students.  I teach 6th grade, except for Social Studies, and 7th and 8th grade Science.  This is my third year teaching the middle school curriculum for LabLearner.  Being a kinesthetic learner myself, I love the lab base approach.  I also love this program from a parent standpoint.  My children are in preschool, first grade, and third grade, and they are already loving science and using terminology that I didn’t use until much later.

Dr. Christine Jurasinski                     LabLearner Staff Scientist

Interdependence.  It’s a word that comes up when talking about virtually everything in today’s world, from climate change to the global economy.  When students in the LabLearner Program hear it they are likely to think about ecosystems and the relationship between producers, consumers and detrivores (decomposers such as scavengers, and microbes), and between prey and predator. For 4^th grade LabLearner students, interdependence is explored through their study of food chains and food webs in the Ecosystems and Adaptation CELL. 8^th grade LabLearner students take this knowledge farther investigating the flow of energy and biomass within ecosystems in the Ecosystems CELL. In addition, both elementary and middle school LabLearner students focus on how competition between herbivores or predation of herbivores by carnivores could increase or decrease the production of producers.  For example, the more herbivores killed by carnivores or omnivores, the fewer herbivores to consume producers and the more producer biomass that will result.

This concept of the effect of competition and predator/prey relationship on producers has long been thought to be the mechanism by which carnivores influenced the diversity and abundance of producers in ecosystems.  Now, new research from wildlife biologists at Michigan Technological University has suggested that carnivores may have a more direct and important effect on producers and the diversity of producers within ecosystems.

Joseph Bump, Rolf Peterson and John Vucetich have been studying the relationship between two parts of the ecosystem at Isle Royale National Park in Michigan: moose (herbivores) and wolves (carnivores).  Their most recent findings have produced what they describe as a somewhat surprising link between the prey/predator relationship and the producers in the ecosystem.   Bump, Peterson and Vucetich studied a 50 year record of the moose/wolf relationship that included observing the location of over 3600 moose carcasses. In addition, they conducted a 3.5 year study that compared the plant growth, soil microbes and fungi,  and nutrient deposition in plant leaves and soil from control sites and those containing carcasses of wolf killed moose.  Control sites were those that did not have moose carcasses. What they found was that soil at the wolf killed moose sites had 100 to 600 percent more potassium, nitrogen and phosphorus than soil at the control sites.  In addition, plants from the wolf killed moose sites possessed 25 to almost 50 percent more nitrogen than plants from control sites.  Bacteria and fungi were also higher at the wolf killed moose sites than the control sites.

When they combined this data with the 50 year record of moose carcasses what they found were “hot spots” of forest fertility- places in which nutrient, microbe and plant life were enriched.   In essence, the researchers say that the wolf/moose prey/predator relationship created a cycle in which the decomposition of moose carcasses increased the nutrient deposition of the soil, resulting in an increase in the amount of plant (producer) biomass and an increase in the nutrient composition of the plants.  Moose, which are attracted to nitrogen rich plants, were then drawn to these nutrient rich locations, depositing feces and urine further increasing the nutrient deposition into the soil.  In addition, the increase in moose frequency to these areas increased the likelihood of predation by wolves and ultimately the increase of even more moose carcasses.

While these findings may seem intuitive, they are shockingly new to the study of ecosystems, which up to this point, has not had evidence of such a direct relationship between predators and soil fertility.   In addition, the finding also suggests that there may be a direct relationship between predator activity and producer (plant) diversity because changes in nutrient availability often promote competition between different tree seedlings.  Thus, the diversity and location of producers within an ecosystem may be directly related to predator behavior – a relationship that once seemed as unrelated as oil and water.  Now, it’s just another example of interdependence.

Dr. Christine Jurasinski                         LabLearner Staff Scientist

What images does the word “fungi” bring to mind? Well, chances are they’re not images of weathering or erosion. Yet, a recent discovery by researchers in Great Britain has shown that fungi play a significant role in the erosion process.

For years, scientists have known that the roots of plants and trees contribute to the erosion of rock. Ask a 6^th grade LabLearner student about the causes of erosion and weathering of rocks, and tree roots are likely to be one of their answers. However, unlike the answer to “what is a cause,” the answer to “HOW do roots cause erosion” was not known. That is, until recently.

Dr. Bonneville and colleagues from Leeds University in Great Britain set out to answer this question. They investigated the erosion of rocks by plants on a nanoscale. Remember, that the prefix “nano” means one billionth of something, so the events and processes they investigated were not something that could be seen by the human eye or even a compound microscope. When analyzing their results, they used an electron microscope to view changes in rocks. What they found was that fungi on the roots of trees caused the physical and chemical breakdown of rocks, something long hypothesized, but never shown.

So, what exactly happens on the nanoscale when plant roots invade a rock? First, it’s important to remember that almost all plants, including trees, have fungi called mycorrhiza that grow on their roots. Dr. Bonneville and his colleagues created an experiment that modeled this. They obtained a pine tree seedling with mycorrhiza on its roots and placed it in a transparent pot containing nutrient-poor soil and a specific kind of mineral called biotite. Biotite is a mineral commonly found in rock and it is rich in potassium, iron and magnesium. No other fungi or microorganisms were in the soil or on the roots. Then the researchers waited three months. After three months they examined the biotite along a single root using an electron microscope. They found that the biotite at the tip was bent as a result of mechanical pressure from the fungi, a pressure that can reach as high as the pressure in a car tire. This pressure if you think about it, is pretty amazing since the mycorrhiza are microscopic organisms. After performing other tests, they found that the fungi had also chemically altered the biotite, removing its potassium and causing the break-down of the biotite into other soil minerals, vermiculite and ferrihydrate.

Their results suggest that at the nanoscale, tree and plants roots cause erosion of rock through both physical and chemical means. The fungi bend and weaken the crystal structure of rock first and then chemically alter its composition by removing potassium. In addition, the wedging and bending of the biotite’s crystal structure allows other iron compounds in the rock to chemically react with oxygen in the air. In the end, the potassium and other released nutrients are passed onto the roots of the trees or plants and the area around the root that was once rock becomes soil.

For LabLearner students these experiments bridge some of the concepts they learn in the Weathering and Erosion CELL and the Classification GAP Unit. In the Weathering and Erosion CELL, students investigate differences between physical and chemical weathering and erosion of rocks. In doing so, they learn that in nature both types of weathering and erosion occur and that physical weathering and erosion aids chemical weathering and erosion by first breaking down rock into smaller pieces that can be more systemically “attacked” by chemicals. In the Classification GAP Unit, students learn about various multi-cellular organisms, one of which is fungi. They also learn about some properties that are characteristic of fungi, including a symbiotic relationship with other organisms such as plants, and the secretion of enzymes that breakdown matter in their environment.

In the past, students may not have linked the concepts described above together. This latest research, however, illustrates once again that LabLearner students will benefit from exploring all areas of science and hopefully finding new and intriguing connections between them.

Dr. Christine Jurasinski                             LabLearner Staff Scientist

For third, fourth and eighth grade students in the LabLearner Program, learning about charges and circuits means learning about electricity. From electrical power plants to microchips, electricity has been one of the mainstays of our world’s technology and a key component in telecommunication devices. A recent discovery from scientists at Yale University, however, may pave the way for that to change.

Dr. Hong Tang and a team of researchers at Yale University work in a field called nanophotonics. To understand what that means let’s take the word “nanophotonics” apart. Photonics describes technology that uses light to transfer information. Fiber optics, optical scanners, lasers, and satellite imaging are all examples of photonic technologies. What makes ‘nanophotonics” different is that the technological research or applications occur on a much, much smaller scale. “Nano” literally means one billionth of something. For Dr. Tang and his team, their research in nanophotonics deals with silicon microchips. Recently, these scientists made a discovery that may allow silicon microchips and other nanodevices to work using light rather than electricity.

So, why is this exciting news and what may this mean about what LabLearner students learn about electricity?

What’s exciting is that Dr. Tang and his associates discovered a repulsive and attractive force of light. Since about 2005 many scientists have theorized that small beams of light could attract or repel each other when placed very close together- such as on a silicon chip. This attraction or repulsive force was proposed to be similar to the electromagnetic forces that occur between positive and negative charges, a phenomenon that LabLearner students investigate in the Exploring Electricity CELL in third grade and the Electricity and Magnetism CELL in eighth grade.

Now, however, that phenomenon is no longer theory. The researchers at Yale University showed that they can produce a beam of light on a silicon microchip that has a repulsive force and a beam of light that has an attractive force. What’s more they showed that that both beams of light could physically MOVE very small switches called nanoswitches in circuits on the microchip, turning circuits in the microchip on and off.

Does this mean that soon we’ll be able to take flashlights and move objects around? An interesting thought, but no. These newly discovered optical forces are very strong on the nanoscale, but too weak on much larger scales. For example, even focused light such as that found in two laser pointers can’t cause the laser pointers to attract or repel each other.

However, when you think about the type of energy and scale that is involved in something like fiber optic communications, this discovery could be potentially revolutionary. The reason is that many technologies such as fiber-optic communications work by converting light signals into electrical signals and then converting the electrical signals back to light signals, all on a micro and nanoscale. This new discovery suggests that light alone could be used to manipulate signals and move switches. This would make telecommunication and other nanodevices like microchips much, much faster and cheaper.

And what about those LabLearner students? Will this leap in technology make learning about electricity a thing of the past? As with all new technology and with all areas of science, understanding basic principles provides a solid foundation on which to build. Although the repulsive and attractive forces of light are a new and complex discovery, the basic principles of attraction and repulsion remain. These principles are the basis of students’ experiments about static electricity in the third grade CELL Exploring Electricity. In this CELL, students explore what is meant by positive and negative charges, and attraction and repulsion. Through their experiments they see and FEEL a very tangible example of how difference in charges can create at attractive or repulsive force. It is this type of knowledge that sets the stage for understanding what is meant by an attractive or repulsive force of light. As students move into fourth grade they explore energy transformations in the Forms of Energy CELL. Understanding that energy is neither created or destroyed but only changes forms can help students understand the energy transformations of technologies like fiber-optics. Finally as students move into eighth grade and the Electricity and Magnetism CELL, they begin to combine mathematical formulas with tangible evidence of electric and magnetic attractive and repulsive forces. The basic foundation about charges, attraction, repulsion and forces that they build through the LabLearner Program may just lead them to be the designers that harness the attraction and repulsive forces of light in the decades to come.