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Posts Tagged ‘ngss’

junk-hat

A hat created by Justin, one of my STEAM it Up students. It is made of upcycled and repurposed materials.

At the beginning of the school year in my STEAM it Up class I had the students vote on which of many possible projects they wanted to work on. The one unit they all agreed on was to make a series of sculptures or cosplay items out of repurposed, upcycled junk. I’ve been collecting materials for years, ever since I created my first “junk” sculpture at the age of 18. I’ve taught this unit three times before in Intersession classes and afterschool clubs when I was at Walden School of Liberal Arts. The results were mixed – the high school students did fairly well, but not so much the middle school students. It seems at that age students are much better at tearing things apart than at systematically planning how to put them back together.

junk-cat

Small junk sculpture of a cat, made by Emily.

My main reason for teaching the class was to actually use up the junk I’ve been collecting and clean out my workshop. Yet it seems I wind up with more stuff before than after – maybe because of the aforementioned “tearing apart” proclivity of middle school students; what was nicely compacted as old VCRs and DVD players is now a series of scattered pieces.

bracelet-and-diagram

A bracelet and a diagram, created for my STEAM it Up class.

So I was a bit reluctant to do this again and bring in boxes of materials that inevitably make a terrible mess in my classroom. But I also knew it could be fun and educational if done right, so I took the chance. I structured this differently than before: each student would need to produce three items. The first would be a small sculpture as a beginning exercise, something that can be easily held in one hand. The second would be a cosplay item or some type of costume piece or wearable sculpture or prop. The third would be a group project where all eight students would plan out a large-scale sculpture together. The second and third projects needed to be sketched out and planned in advance.

little-man

A little man, made from old keys and other recycled objects. Glued together with hot glue and E-6000 adhesive.

They came up with a variety of interesting sculptures for their first and second projects, as seen here. I am also including some of their sketches, although in too many cases they drew the sketches after they made the sculptures. Some of the sculptures involved LED lights, which took some planning and thinking through. The point is to teach them some engineering and materials science skills, and engineers plan everything out in advance. Some students resist this, as they see these sculptures as art forms, not engineering designs, and pre-planning seems to them to impede the creative process. Of course, without planning and thinking through how to attach the disparate materials together, their sculptures tend to fall apart. Glue alone can’t hold a load-bearing member like a leg or arm.

small-soldier

A tiny soldier, made by Noah for my STEAM it Up class.

Which is why we are doing a group project. We decided to build a futuristic Mars colony city (to go with our school’s overall Mars Exploration project – more on this coming in my other blog at http://spacedoutclassroom.com).

space-ship

A space ship sculpture, made from recycled motherboards and other electronic junk.

Two years ago, we had someone contribute a lot of materials to Walden School that were from a doctor’s office or scientist’s lab. I still have no clue what most of the stuff was even for – some of it is probably valuable as antiques. One item was a still for making distilled water, but bought in the early 1970s because of its horrible avocado green color scheme. I managed to get a chemistry professor at Brigham Young University to take it off my hands. But the rest of the stuff was of little use. One item was a plastic autoclave, with multiple levels for sterilizing surgical equipment. There were also glass containers for storing or cleaning microscope slides (I think – based on similar plastic items I’ve seen in the Flinn Scientific catalog).

flying-saucer

A flying saucer that lights up, made by Sam for my STEAM it Up class.

The autoclave looks like a domed city, something out of Isaac Asimov’s Caves of Steel series of books about the android R. Daneel Olivaw and Detective Elijah Bailey. We were looking at the autoclave and other materials and “noodling around,” which is an important scientific and engineering creative process: putting things together that don’t normally go together and seeing what would look good and work toward a harmonious whole. We came up with the glass containers as pillars for the autoclave layers. One of the students suggested offsetting the layers. I sketched these ideas out on my whiteboard, and we worked through how to attach everything together using metal piping from old 1980s brass and glass furniture with bolts and L-brackets, and wire to tie the pillars together to make the whole thing structurally sound.

bracelet-with-led

A steampunk bracelet with LED light, made by Sam.

Teams of students took different layers. The bottom layer (Level 1) will be the industrial and manufacturing center, so one team is making industrial-style equipment and buildings that look like factories and power plants. One team is doing Level 2, which is the main residential sector. One team is doing Level 3, which is the administrative, shopping, hospital, and school level. They built a school from an old calculator and wanted the holes to become solar panels. I remembered having a folder with a shiny metallic-blue cover, so we cannibalized it to become the solar cells. Level 4 is the park, university, and upper class residential sector, and the dome will have spaceports, defense, and communications centers. Already the pieces are shaping up. This is exactly the engineering and materials science I had hoped for when we started this unit.

magic-wand

Magic wand, made by Sarah for my STEAM it Up class.

We are now beginning the construction of the main city levels, but Winter Break has halted the process. It will be our last project for the STEAM it Up class. It will sit upon two wooden plaques, again donated from the doctor’s office, and we’ll create smaller domes for hydroponics and farms, with small Mars rovers (already made by one student who is great at miniaturized sculptures).

stamp-and-ring

Small sculptures created by my STEAM it Up students: a stamp and a ring.

We’ll make Mars landscaping from paper maché and HO scale model train decorations. I also hope to put wires up through the support shafts and add LED lights to the city. The final city will be quite heavy and hard to move around, so it will stay in my classroom and make a great decoration for my newly completed lab. We’re photographing the construction process, I’ll interview the students, and we’ll add all of this to our ongoing Mars project documentary video. I’ll write another blog post in January when we can show the finished sculpture. I would also like to create a virtual 3D model of the finished city so we can animate and label the parts.

mars-colony-sketch

First drawing of our Mars colony, using parts from an autoclave as the levels of our city and glass microscope slide cleaners as pillars.

We still need to pick a name for it. Looking up names for Mars in various cultures, and adding translations for the word “city,” I come up with some possibilities: Aresdelphia, Al-Qahira Madina, Harmakhis Delphi, Hradelphia or Hrad K’aghak’, Huo Hsing Shr, Ma’adim Delphi, Kaseishi, Mangalakha, Martedelphia or Marte Cuidad, Mawrth Dinas, Nirgal Alu, Shalbatana Alu, Simudelphia, Labouville, and Tiuburg. We’ll have to vote on it.

mars-colony-first-attempt

Even without glue or bolts, the layers stack up fairly well in this first attempt to build the Mars colony city. We decided to use two of the boards instead of one so we could add more landscaping and farming domes using HO-scale model railroad decor.

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rabbitbrush-with-mountain

Rabbitbrush blossoming in October in the southwest corner of Salt Lake Valley, Utah.

In my STEAM it Up class at American Academy of Innovation, my students have conducted an inquiry lab that combines chemistry and technology with history and an ancient art form: dyeing cloth. I reported on a similar lab two years ago, but we have taken it much further and created an investigation that would work well for all chemistry classes without requiring too much equipment or expense. This activity fits in well with the NGSS dimension of science and engineering practices, as it allows students to identify variables, create experimental procedures, collect data, and report results in a fun and engaging way that incorporates art and the history of chemistry. Since dyestuffs are found around the world, there is also a global education component.

collecting-rabbitbrush

My STEAM it Up students collecting rabbitbrush blossoms near American Academy of Innovation (the bright orange building in the background).

We live in Utah, and there are a number of dyestuffs available that were used by Native Americans. Some materials, such as cochineal, were imported and traded for from as far away as modern day Mexico. Others are native to Utah, such as rubber rabbitbrush or Ericameria nauseosa. Our new school was built in a grassland area in the west side of Salt Lake Valley that was formerly used by Kennicott Copper Corporation (now Rio Tinto) as a mine and waste dump. After millions of dollars in cleanups, the site is now the new planned community of Daybreak, and our school is on the west edge near the South Jordan Trax Station. Since it is a former prairie, rabbitbrush grows around us in the empty lots right next to our school.

cutting-rabbitbrush-blossoms

Preparing rabbitbrush blossoms for dyeing.

I had read that marigold blossoms make a good dyestuff, so on the day of our first attempt, I snipped half the blossoms off my marigold flowerbed (which grew up from last year’s seeds). My students and I took a mini field trip about 50 yards from the school where rabbitbrush was growing. It was the end of September and the brush was just beginning to bloom with bright yellow flowers in clusters. We collected several buckets. The species name of nauseosa is well earned, as the smell is a bit nauseating (some students are more sensitive to it and can get itchy eyes, so be careful of this). We also had walnut shells, cochineal, and the marigold blossoms as our dyestuffs.

rabbitbrush-blossoms

Rabbitbrush blossoms ready for boiling in the dye bath.

Students teams of two each decided on a variable to test, such as the type and concentration of dyestuff; the type and concentration of mordant (a mordant is a metal salt such as sodium carbonate [washing soda] or alum powder [hydrated potassium aluminum sulfate]) that helps the dye bind with the fabric threads); the temperature and duration of the dye bath; and colorfastness (if the dye holds its color upon washing). They determined a procedure for testing their one variable while holding the rest constant. We then dyed small swatches of white terrycloth washcloths. A further variable could be the type of fabric used, but I only had the terrycloth for now. I hope to order some untreated cotton and wool yarn and dye them as well.

rabbitbrush-and-marigolds

Rabbitbrush and marigold blossoms ready for dyeing.

Our basic procedure was to boil two Pyrex dishes half full with water. To one the mordant was added, to the other the dyestuff. The cloth swatches were first boiled for 10 minutes or so (depending on the group’s procedure) in the mordant, then the swatch was added to the dye bath.

cooking-rabbitbrush

We soaked white terricloth pieces in a boiling alum solution (the mordant), then boiled them in the rabbitbrush dyebath.

The results were excellent, and we were careful to label all the swatches with Sharpie permanent markers so that we could make comparisons after. We cut the dyed swatches in half and I washed one half at home in my washing machine. Each swatch was scanned into my computer and the eyedropper tool in Adobe Photoshop (you could use the Gimp as well) was used to sample three places on each swatch and record the RGB values. We averaged the values, and compared them to see which combinations of variables gave the best results.

dyeing-with-cochineal

We also dyed terricloth swatches with cochineal and an alum mordant.

We also tried adding more than one dyestuff to the same bath (doesn’t work well) and overdyeing, that is, dye a swatch with one color, then put it in a different color. We also tried an ornamental plant that was growing around our school, which I call firebrush; it has green to pink-red leaves (older interior leaves are more green). The firebrush provided great pigment upon boiling, and turned the cloth a nice pink color, but when rinsed out, the color gradually changed to a medium green. I suspected it might be a pH indicator, so I dipped part of one green swatch in vinegar and found it turned bright pink again. Only those two colors – green when neutral, pink in an acid. But it is apparently a good indicator and a fairly colorfast dye.

first-swatches-2016

Our first dyed swatches, labeled with permanent marker. The left swatch is rabbitbrush, the second is marigolds, the third is cochineal without any pH modification, the fourth from left is cochineal with Cream of Tartar added, the last (right) swatch is cochineal with vinegar added.

As a further experiment, we tried adding Cream of Tartar or vinegar to the cochineal to see if we could turn it from magenta-burgundy to more of a bright red color or even orange, with mixed success. We got a bit more reddish color with Cream of Tartar, but never got to orange. Reading websites and other sources, I found that we need a stronger organic acid that wouldn’t dilute the dyebath, such as citric acid. To turn the cochineal more purplish, ammonia can be used. We also tried cochineal with rabbitbrush but still did not get an acceptable orange – just a salmon pinkish color. We need orange because our school colors are Innovation Orange (you can see our building from miles away, as the photos show) and Titanium (we are the Titans). We could also some other dyestuff, such as madder root, sandalwood, or safflower.

swatches-2016

Swatches from our dye experiments. The ones on the bottom are pieces that have been washed to test colorfastness. The brown swatches are from walnut shells and hulls soaked in water over several days. Other swatches test different types of mordants (alum versus soda ash versus Cream of Tartar) or different concentrations of dye.

We experimented for several weeks with different combinations and the students wrote up their final conclusions. Here is what we learned: The best mordant for rabbitbrush, marigolds, and cochineal is alum powder. Cream of Tartar tends to gladden (or lighten) the colors, whereas soda ash (sodium carbonate) tends to darken or sadden the colors. Cochineal was less colorfast than we expected based on previous experiments, and tended to bleed all over the other colors when washed. Walnut shells seemed to do best with soda ash as a mordant. Overdyeing was only partially successful; we were trying to get a good orange and never did. The marigolds didn’t make a good orange either – but did do a nice golden brown color. Walnut shells with rabbitbrush made a nice golden tan, but cochineal with rabbitbrush depended greatly on which was dyed first; the overdye tended to eliminate most of the first dye.

fireweed-results

The results of our experiment with firebrush, an ornamental shrub with green inner leaves and scarlet outer leaves and wicked thorns. The dyebath was bright pink, as in the swatch second to left, but when rinsed out it turned green as in the swatch second from right. I took a rinsed green swatch and dipped it in vinegar and the bottom turned pink again. Firebrush is apparently a pH indicator.

A final variable is to test different fabrics. I ordered more dyes, including madder and indigo, from Dharma Trading Company in November as well as untreated merino wool yarn and cotton cloth, with more alum powder and citric acid. Adding the citric acid to the cochineal did indeed turn it red (and eventually orange). Adding ammonia turned it purple. It worked wonderfully on the untreated wool yarn; I dipped one end in the regular cochineal and the other end in the cochineal with citric acid and got a beautiful variegated red to burgundy-crimson skein that held its color well upon rinsing and washing. The cotton cloth didn’t hold as well; I make the cloth purple to orange and even let it set overnight in the dyebath, but upon rinsing all the cloth turned back to a light magenta. The rabbitbrush made a nice soft yellow for the merino wool yarn.

cochineal-dyed-yarn

Merino wool yarn dyed with cochineal. I varied the pH by adding citric acid to get the brighter red colors, and dyed one end of the skein with regular cochineal and the other end with citric acid treated cochineal to produce variegated yarn. Now to crochet it into a sweater . . .

My wife is amazing at crocheting, and my ultimate STEAM art product will be for her to use our naturally dyed merino yarn to create a sweater and a beanie. I also want use the dyed pieces of cotton to make a quilt in the shape of our school logo. I know several professional quilters who can do this for us. If the cotton isn’t accepting the dyes, then I must experiment further. Perhaps I didn’t soak the cloth in the mordant bath long enough. I am still experimenting with getting blue colors from woad and indigo, but more on this in a later post.

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Set up for the stop-motion animation activity. You will need a solid tripod, a black-topped table with good lighting, and rulers to mark the edges of the stage area (camera field of view).

Set up for the stop-motion animation activity. You will need a solid tripod, a black-topped table with good lighting, and rulers to mark the edges of the stage area (camera field of view).

As part of the STEM-Arts Alliance program I’ve initiated at Walden School of Liberal Arts, I am always trying to find activities in my science classes that can integrate art, history, and/or technology. At the NSTA national conference in San Antonio in 2013, I attended a session by Dan Ratliffe from the Breck School in Minneapolis on using stop-motion animation techniques to model a chemical reaction, in this case the burning of methane. He showed how to set up a stage, use student groups and manipulatives, and how to show how energy is absorbed (activation energy) to start the reaction and how energy is released. He uses it in his 6th grade science class, but I’ve adapted the lesson for use in higher level science classes such as chemistry or physics or astronomy.

Animation stage (marked with rulers). Since the camera couldn't point straight down, the stage is a trapezoid. On the large sheet of paper is our storyboard/plan.

Animation stage (marked with rulers). Since the camera couldn’t point straight down, the stage is a trapezoid. On the large sheet of paper is our storyboard/plan.

On Jan, 31 this year, I needed to make one of these animations for a demonstration I was doing at the UACTE conference. My chemistry students were studying nuclear chemistry and nuclear reactions at the time, so without any warning to them, I announced we would be making an animation of the nuclear fission of Uranium-235. I had cardstock and permanent markers already in the room, and brought my camera and tripod to class. My small class of students were able to create all the drawings and labels, plan the sequence, and do the photos all in one class period plus a few minutes after school to clean up, so about 80 minutes total. It wasn’t anything too fancy, but it worked. That evening I dropped the images into Apple Final Cut Studio (setting each image to last three frames), then dropped them onto the timeline, expanded them all together so the edge of the stage wouldn’t show, and exported it. I didn’t try to add narration or sound effects, but it did the job. Then I demonstrated the process at the conference the next day.

This lesson meets standards HS-PS1-8 of the Next Generation Science Standards to model nuclear reactions as a core idea in chemistry. I have written it all up as a PDF lesson plan. I’m including the process steps here, but you can download and use the lesson plan here: Stop-Motion_Nuclear_Reaction

Objectives: By the end of the activity, students will be able to:

  1. Create storyboards and sketches showing the stages of a chemical or nuclear process;
  2. Set up a stage and move objects around from frame to frame to demonstrate the process;
  3. Edit and align sequential images in an image editing software package;
  4. Import a series of still images into video editing software and export the sequential images as a continuous animation.

 

An early frame for the animation. A neutron (red bead) approaches an atom of U-235.

An early frame for the animation. A neutron (red bead) approaches an atom of U-235.

Materials for each group:

Regular unlined copy paper (for storyboards)

Cardstock paper (for labels)

Marker pens or colored pencils

Balls of different sizes to represent large uranium atoms, smaller fission products, and

neutrons. You can use poker chips and tiddlywinks instead.

Scissors

Clear tape

A black-topped lab bench or table with a black tablecloth

A digital camera and tripod that can look down on the table without seeing the edges

Meter sticks and smaller metric rulers

Computer with video software

 

The first atom of U-235 splits into Barium and Krypton plus energy and two additional neutrons.

The first atom of U-235 splits into Barium and Krypton plus energy and two additional neutrons.

Step One: Introduction

Introduce this lesson by showing your students some examples of stop-motion animation and discussing how traditional animation was drawn frame by frame on acetate sheets. Explain that they will be creating their own animations in groups.

Review the types of nuclear reactions that are most often learned in a unit on nuclear chemistry, such as the fission of Uranium-235; the fusion of hydrogen; nucleosynthesis inside a star; the conversion of a neutron to a proton, anti-electron neutrino, and beta particle through the weak nuclear force; the beta and alpha decays of various elements; the conservation and conversions of energy and matter in a nuclear reaction; etc. List these reactions on your whiteboard. Assign students to groups of 4 to 5, and have each group pick a different reaction.

 

The three neutrons travel on toward three more U-235 atoms.

The three neutrons travel on toward three more U-235 atoms.

Step Two: Planning the Animation and Creating the Pieces

Divide the students into groups and provide them with the materials they need. For this first period (initial 45 minutes) they will research the relevant reactions, draw out a storyboard or plan for the steps of the process, write a narration script (optional), then create the pieces they need. They can represent atoms or subatomic particles by balls or paper drawings on cardstock. If they use balls, they should create paper labels for each object. Energy can be represented in different ways, such as drawing lightning bolts or gamma rays or bursts of energy.

Give the students encouragement and suggestions as needed, but allow them to use their creativity and have fun with this activity. They may want to bring in their own props. The final storyboards and animations should be scientifically accurate and demonstrate deep knowledge of the reaction they choose as well as be aesthetically pleasing and well designed. They should also create titles and show the reactions as equations. By the end of 45 minutes they should have their plans complete and their pieces, labels, and drawings finished and cut out.

As an option, you may want each group to write up a narration script and record the narration using a microphone. If you do this, then allow for an additional class period. The final animation will have to be carefully timed to match this narration.

 

The three atoms of U-235 split to create new byproducts, more energy, and a total of nine neutrons.

The three atoms of U-235 split to create new byproducts, more energy, and a total of nine neutrons.

Step Three: Filming the Animation Frames

To set up the animation, a camera should be mounted on a tripod or other solid structure and placed so that its field of view encompasses a black lab bench or table topped with a black tablecloth without seeing any edges. To find out the exact area of this “stage,” use meter sticks or other straight edged objects and move them in on all four sides of the camera’s view until you can just barely see them at the edge of the view. If your camera is facing straight down, the stage will be a rectangle, but this is often difficult to achieve without making a special frame or mount for the camera. If it is on a tripod, then it will be looking at the stage at an oblique angle and the stage area will be a trapezoid. Once the stage area is set and the camera is in place, they must not be moved.

To film the frames, have one student assigned to use the camera (and not bump it or move it between frames). The other students will move the pieces. They will want to practice the process, deciding how far to move each piece between frames. A good frame rate for the final video would be 10 images per second. Since digital video plays back at 30 frames per second, this means one image will be three frames long. This means for a 10 second animation, you will need to take 100 photos. If each piece is moved too much between images, the resulting animation will be jerky and too fast. If it is moved slower, the resulting animation will be smoother but you will have to take more photos. The amount of motion between frames should be consistent or the movement will seem to speed up and slow down for no reason. Students should use a ruler to measure the distances to move objects between frames exactly. Objects such as atoms that need to stay in place for several seconds can be taped down with clear tape.

Once they get going, the group can develop a kind of rhythm. They will stand around the stage with the camera operator calling out, “Move. Clear! Move. Clear!” and taking photos as the students clear out, then move their assigned pieces as planned. A student should also be assigned as the Director to ensure the storyboard is followed and object placement is correct from frame to frame. Labels should be used for all parts, such as neutrons, atoms, energy, equations, titles, etc. When an atom is split or atoms fuse, if energy is released, it can be shown appearing and moving outward from its origin or creating a flash. Byproduct particles can then move on to collide with other objects. For example, if you are splitting U-235, then a neutron enters, collides with an atom of U-235, which splits into two products (there are several possibilities, such as Krypton-89 and Barium-144, or Xenon-143 and Strontium-90, etc.) along with two new neutrons and gamma radiation. A chain reaction can be demonstrated going through several steps. They could even show a mushroom cloud at the end.

Special effects can be created, such as blinking objects (having an object appear in one frame, then disappear in the next, and alternate – it will appear to blink or flash in the video). With a little practice you can get the timing right. You can create explosion graphics and add white or colored frames to simulate a flash of energy. If your students know how to use image software to create alpha channels, then separate images can be filmed and added with transparency to the final video as layered animations. In the end, the only important things are to keep the motion smooth and consistent, don’t bump the camera, and don’t get anyone’s hands in the photos.

 

The nine neutrons travel on to split nine atoms of U-235 and release even more energy and more neutrons . . . thus becoming a chain reaction that will result in a nuclear explosion if left unchecked. Labels and equations can be added as the final particles migrate off the stage.

The nine neutrons travel on to split nine atoms of U-235 and release even more energy and more neutrons . . . thus becoming a chain reaction that will result in a nuclear explosion if left unchecked. Labels and equations can be added as the final particles migrate off the stage.

Step Four: Creating the Video

The photos will need to be uploaded to the computer which has the video software. Ideally each group should have a computer capable of doing this; almost any video software including iMovie and MovieMaker will work. There are apps available for iPads or other tablet computers such as iStopMotion. As you import the images, make sure they are numbered sequentially. Most digital cameras will do this automatically.

If there was any bumping of the camera, then the images may need to be aligned or registered using image editing software. Each image can be imported as a separate layer and moved around to align it with the rulers seen along the edges in the bottom layer. This will be a tedious process, so it is far better not to bump the camera in the first place!

If the photos are well aligned, then you can import them directly into your video editing software. Some programs allow you to set the length in frames of each imported image. You would want to set the images to three frames each if your final frame rate is 10 images per second. Once imported, if they are numbered sequentially, all you need to do is select all the images and drag them to your timeline in the video software and they will be in the right order and length.

Since the rulers can be seen along the edges of each image, you will need to enlarge the images. This can be done in two ways. The first is to expand the first image, then apply the same settings to each subsequent image. This is a slow and boring process. It’s much faster to simply export the video as is, then open a new file and import the draft video and place it on the timeline. Then the entire video as a single clip can be expanded to move the rulers off stage, and the final video exported again. You can add special effects (inserting flash frames, titles, additional layers, etc.), add narration and/or music and sound effects, and export the final version.

 

Step Five: Evaluation

Once the videos are done and ready to view, give the students feedback forms that ask them to evaluate the final videos, including their own, on such areas as scientific accuracy, depth of knowledge, technical ability, and aesthetics/design. Leave room for comments. Show the animations to the class, and have them fill out a feedback form for each video, encouraging the students to make positive suggestions. Then collect the forms and tally the results as a final grade for the assignment. You will want to evaluate the videos yourself as well and give more detailed feedback on how they can improve. You could also create a master video by piecing all the group projects into one video, then upload the whole thing to YouTube so other schools/classes can view it.

 

Notes on this Lesson:

This idea could also be used to model any process or natural cycle, such as chemical equilibrium, phase changes, types of reactions, conservation of matter and energy, kinetics, pH titrations, and thermodynamics in chemistry and the rock cycle, the water cycle, the carbon cycle, stellar evolution, plate tectonics, etc. in other sciences. I would enjoy hearing your ideas. Please let me know how you are using this activity by e-mailing me at: elementsunearthed@gmail.com.

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