Posts Tagged ‘chemicals’

Blue gak

Blue gak, part of a student demonstration

Last December right before winter break, my chemistry students prepared demonstrations to present to each other and to the elementary classes here at Walden School. This was their first attempt at it, and they received evaluations from me and from their peers with suggestions on how to improve. Now we have just finished the second round of presentations, and each team has added new features and made improvements.

Green slime

Green Slime

I had each team improve their presentations in four areas: first, their presentation skills, such as speaking with good diction, showing enthusiasm, and having a smoothly scripted and rehearsed narrative. The second area was improving the visual appeal of their presentation by adding some sort of poster or handout that could be used as an activity for the audience while the team sets up. Some of the groups made posters, some made paper games such as word searches or worksheets. The third area to improve was to add a multimedia component, such as a powerpoint slide show, a video, or a game. The final area for improvement was to make their presentation more hands-on for the audience, such as having more audience participation, or some sort of kinesthetic activity, or turn the presentation into an inquiry-based lab.

Girl with pH samples

Girl with pH samples

The results were very good; all the presentations have improved. Their science content was already good, but is deeper and more engaging now. By adding slide shows, posters, games, activities, and participation, they have gotten their audiences much more involved and excited.

Here are some examples: One group presented on the properties and uses of silver, and their demonstration was how to untarnish silver. They not only had a good slide show, but created a kinesthetic activity where the elementary students linked arms to form first silver sulfide (tarnish) and aluminum, then reformed to create aluminum sulfide and pure silver. This demonstrated the idea of conservation of matter in chemical reactions.

Sofia activity

Sofia leads a kinesthetic activity

The cabbage pH group turned their presentation from a demonstration into an inquiry lab by pouring samples of many types of household chemicals and food (such as grapefruit juice) into small clear plastic cups, then having the elementary students predict whether the chemicals were acids or bases, then use the cabbage juice to prove their guesses.

Marni and kids

Testing the pH of household chemicals with cabbage juice

My favorite improvement was in the saltwater density group; they had some difficulty during their last presentation with not having practiced enough and having things not work out as planned. This time it went smoothly, and they even created a computer video game called Salt the Slug. Jess created the graphics and Josh did the programming. The purpose of the game is to use the trackpad of the computer to shake a salt shaker up and down, shaking out salt onto a slug that is crawling across the screen trying to steal food. If the player can kill the slug before it gets back to its home with the food, he or she wins. Yes, the concept sounds a a bit cruel but it taught the idea of osmosis and concentration of solutions and besides, the graphics were hilarious. The elementary students were jumping up and down for a chance to play, so the team had to ask them some review questions to decide who would get a chance to try the game out.

Slug game

"Salt the Slug" game by Jess and Josh

Josh has become an excellent game programmer and created another game, which he has been working on for a year, where the player places towers that then shoot into a maze to repel invaders. He presented this game at the Charter School Science Fair for all of central Utah, and now has qualified to go on to the regional science fair at BYU in late March. I was a judge at the fair last week, and it was amazing to see the caliber of some of the projects.

Josh at science fair

Josh at the Charter School District Science Fair, Feb. 24.

One of my favorite things about doing these presentations is that many of my high school students have younger siblings in the elementary classes; what better way for my students to show off what they’ve learned, and how they can do science, than in front of their younger brothers and sisters? Dallas, one of the students in the group that demonstrated gunpowder had his little sister in the class. They kidded each other a lot, and Dallas had to tell her, “Don’t get sarcastic with me, I taught you sarcasm!” This group also included a nice demonstration of the “toast the runt” reaction, where potassium chlorate is heated to start it decomposing and giving off oxygen, then a runt candy is rolled down the test tube as the fuel source, resulting in a stationary solid rocket motor.

Toast the runt

Toast the Runt: A Solid Rocket Engine

We had to reform some of the groups, since a few students had switched sections at the semester, but the same presentations continued. Those teams that presented to their peers last time presented to the elementary classes this time, and vice versa. Each team has now presented twice and received feedback. Now they will present one more time at the end of the year at our Mad Science Night, where their parents and siblings are invited and we will take over four classrooms and run simultaneous sessions. It will be a lot of fun, and their presentations will be amazing.

Carbon dioxide and magnesium

Burning magnesium in carbon dioxide gas

Meanwhile, it has been quite a bit of time since my last post. I haven’t been ignoring it; rather, I’ve been so busy teaching, grading, entering competitions (such as the Explore Mars competition I mentioned previously), creating some video projects on the side for clients, presenting at the Utah Science Teachers Association conference (the Mars lessons again), and preparing for my trip to the NSTA conference next week that I simply haven’t had a chance to do many blogs. However, I have quite a backlog of student written blog posts that I will be adding over the next week, then posting each day from San Francisco, so you’ll see quite a few posts this month.

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   There are four reasons why The Elements Unearthed project is needed. The first is for our own self-protection. The second is to protect our heritage and history. The third is to protect our future. The fourth is to protect our country’s standing as the leader in science and engineering innovation.


1.)    Our own self-protection:

   Our lives are impacted by chemicals, materials, and the elements every day, yet too many people are ignorant of the extent to which we interact with the elements. Let me give three examples.


    A – In the summer of 1978, residents of the small town of Deseret in west central Utah were alarmed to find out that high levels of arsenic had been discovered in their drinking water, at over three times the EPA allowable limit. Each house in the town had  an individual well dug down to an aquifer 186 feet below ground and it was this level that had become contaminated.

Arsenic article in Millard County Chronicle

Arsenic article in Millard County Chronicle

No one knew where the arsenic had come from or how long it had been there. Extensive tests were given to the townspeople. I went through those tests myself, and they were quite uncomfortable – especially the nerve conductivity tests! The original medical study was published in 1982, with inconclusive results. A longitudinal study of mortality rates of people in the area was published in 1998 and showed a correlation between arsenic exposure and increased incidence of hypertensive heart disease, nephritis and other kidney problems, and prostate cancer. My own grandfather, who had lived in Deseret all of his life, died of prostate cancer, possibly as a result of arsenic exposure.



    B – In one week in December, 1996, three separate incidents occurred in Utah that involved toxic chemical spills. The first was a railroad car carrying diesel fuel that spilled its load and caught on fire. The second was an 18 wheeler traveling north on Interstate 15 that blew over in a gust of wind just north of the town of Nephi. It was carrying sodium azide for use in car airbags, and when rainwater mixed with the spilled azide, it burst into flames that were so hot that it burnt a hole down through the roadbed and sent a plume of gray smoke toward the town of Mona. Residents were evacuated and traffic on I-15 was diverted 30 miles out of its way onto an alternate road. The next morning another 18 wheeler spun out on slick surfaces on that alternate route and overturned, spilling its load of sulfur dioxide pellets. Traffic was again diverted onto yet another alternate route over 50 miles out of its way. I was living in Nephi at that time and had to travel these alternate routes to get to work. In Utah they called this HazMat Hell Week.


   C – Growing up in western Utah in the early 1960s, I was exposed to fallout blown downwind from the nuclear testing in Nevada. Since my family milked its own cow that was kept in a pasture behind our house, the cow ate alfalfa that was contaminated by radioactive iodine-133 from these tests, which was concentrated in the cow’s milk. I have been told that I should have my thyroid gland checked regularly in case I develop thyroid cancer as a result of this fallout.


   These are just three of many examples of how chemicals and materials have influenced my own life. Millions of tons of chemicals move across our highways and over our rail system each year. People store potentially dangerous chemicals in their own homes without much understanding of what they are used for or how to handle them safely. Water and food can become contaminated. We need to understand how chemicals work and where they come from if we are to keep ourselves safe. The Elements Unearthed proposes to provide the information that people need on the hazards and uses of chemicals and materials.


 2.)    To save history:

    Human history is tied directly into how well we have understood and used the material world we live in. Epochs of our history are named after advances in materials science, including the Stone Age, the Copper Age, the Bronze Age, and the Iron Age. The Elements Unearthed project intends to dig up the story of how our history and the discovery of the elements have been dependent on each other. Much of the history of the United States has been influenced directly or indirectly by materials and chemicals, by mines and miners, with such events as the Spanish conquest of the western United States, the California Gold Rush, the Comstock Lode in Nevada, the coal mines of West Virginia, the steel mills of Pennsylvania and Ohio, the Pikes Peak rush in Colorado, and the Klondike Rush in Alaska all adding to our national character.


   Yet much of this history is being lost, as mines close and the miners that worked in them die away. Virtually gone are the days of panning for gold or hard rock mining with pick and shovel. Old mine sites are being closed and covered for safety and environmental reasons, and this part of our history is in danger of being lost forever. Our project is needed to preserve this history and tell these stories.

Headframe at the San Francisco Mine, Utah

Headframe at the San Francisco Mine, Utah


3.)    To protect the future:

    As we face tough choices now and in the near future regarding how we use our resources, generate our energy, transport, feed, and clothe our population, and improve our environment, we must have an informed public that can support and vote for the policies that will protect our increasingly fragile world. Resource depletion, environmental degradation, energy consumption, and global warming are daily headline news, and national leadership and public awareness must begin to focus on these issues. Decisions must be made now; we cannot continue to “kick the can” down to future generations. Education and public awareness must focus on accurate, unbiased information, and our project intends to provide that information in various formats and locations that are free and easy to access by the public at large and particularly by high school and college students and their teachers. The solution to this problem of an informed populace lies in education, both formal and informal, and that is the main purpose of our project.


4.)    To protect the U. S. economy:

   The U. S. economy has been the envy of the world for decades. Although it is still very strong, many experts are beginning to see signs that we may not be as competitive in the near future as we have been in the past. The major driver of our current strong economy has been innovations made in the computer industry over the last 30 years, coupled with new technologies that computer control and automation have brought us. Yet to maintain our economy in the future, we must continue to innovate and there are doubts that we will be able to do so, especially as the world economy becomes more globalized and competitive. One of the largest danger signs has been a decline in students prepared to pursue careers in science, technology, engineering, or mathematics (STEM).


PISA Science Data, 2006

PISA Science Data, 2006


   In 2006, 15 year old students in 57 countries around the world were tested on their science literacy by the Program for International Student Assessment (PISA). The average score was set to be 500 out of a total possible score of 1000. The results have been summarized in this chart by region. In science literacy, students in East Asia, Canada, the South Pacific, Scandinavia, and Western Europe all scored significantly higher than students in the United States, who scored 489 or below average. Overall ranking of United States students was 29th out of 57. Students in Russia and Southwest Europe scored slightly below students in the United States with average scores of 479 each. Students in Southeast Europe, South and Central America, and the Middle East on average scored worse than students in the United States.


  The 2006 exam also tested for math literacy and found U. S. students to be 35th out of 57 with an average score of 474 compared to 538 for East Asian countries, 527 for Canada, 512 for Scandinavia, and 510 for Western Europe. Only Southwest Europe, Southeast Europe, South/Central America, and the Middle East regions scored worse that the United States.

PISA Math Test 2006

PISA Math Test 2006



   These scores show that we are not doing well at preparing the next generation of scientists, engineers, and mathematicians. A full 30% of incoming freshmen must take remedial science and math classes just to meet college general education requirements, let alone have the background skills needed for technical majors. In addition to poor preparation and knowledge, fewer students choose to enter STEM professions, with enrollments in science and engineering programs at colleges declining and graduate programs having to look to foreign students to fill their ranks.


   Many U. S. businesses that rely on a steady stream of STEM graduates are already finding it difficult to recruit enough adequately prepared people. For example, NASA hired many aerospace, civil engineering, and materials science graduates during the 1960s and ‘70s. Now almost 40% of NASA’s technical workforce is set to retire in the next 15-20 years, and there are not enough U. S. students in the education pipeline to fulfill the coming shortage, nor is NASA allowed to hire many foreign graduates for national security reasons. In the past, shortages in technical fields could be made up by hiring non-American graduates, but now with security restrictions and new jobs being created in their homelands as a result of globalization, many of these foreign recruits are no longer available. 


   Some businesses are taking matters into their own hands by supporting programs that would help to train their future recruits, such as direct grants to schools, challenge competitions, or teacher professional development programs. NASA has created the NASA Explorer Schools (NES) program to train teams of teachers and administrators from schools and to provide direct grant support to improve their science and technological infrastructure.


NASA Educator Workshop at JPL, 2002

NASA Educator Workshop at JPL, 2002


   As mentioned in my previous post, I have had the privilege of participating in this program, first as a teacher, then as an Educator Facilitator to help lead and plan the workshops at the Jet Propulsion Laboratory. Each year, five teams of five teachers and administrators visit JPL for a week-long workshop. They tour the facilities, meet the scientists and engineers that are designing, building, and running the space probes, learn of NASA’s educational programs through the Education and Public Outreach coordinators for each mission, then work as a team to plan how they will incorporate these experiences into their curriculum. NASA personnel then work with the schools over a three-year period to promote systemic change in the hopes of inspiring the next generation of explorers, scientists, and engineers.


   Our project will encourage students to pursue careers in chemistry, chemical engineering, and materials science by showing firsthand what scientists do, how problems are solved by engineering, and how creative, challenging, and rewarding these careers can be.


   Below is an Enhanced Audio podcast episode describing our project in more detail. Next week we will have additional information and statistics about why this project is so important, as well as a video podcast describing the entire rationale of The Elements Unearthed.


ep-a01 Overview of Project [Enhanced Audio]

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