Curriculum for Teaching Science and Scientific Thinking (Essential Skills Series)

See Essential Skills for a Modern World for an overview of this series on science and critical thinking skills.  I discuss science and scientific thinking in the post Follow the Ant. The recommendations below are based on my experience educating my sons and myself over the last decade. In my next post, I’ll explore other resources for fostering scientific thinking and increasing scientific understanding. 


Okay, you’ve followed the ant. Well, perhaps you’ve considered sending your kids out to follow the ant, asking them to return and fill you in, but hopefully you’re thinking about your children’s science education in more practical terms. Here’s a bit of assistance.

Choosing curriculum

Formal curriculum isn’t the most essential part of a child’s or adult’s science education , but I do know it’s what comes to mind when we think about teaching science. For the youngest students, I’d not bother with formal curriculum. Explore the world together. Follow your child’s interests or introduce him to yours. Go to the library and explore the science sections for children and adults. Watch science shows for kids and for adults, but mostly DO science by interacting with the natural world.

When you start selecting formal curriculum, be choosy. Insist on a curriculum that puts science at the center and avoids other agendas. (The scientific process is quite different from theological thinking. Mixing them makes for a poor education in both. Don’t do it.) Look for curriculum that requires the student to ask questions and to think about possibilities. Many texts intended for schools simply don’t do much of that, nor do many of the big-name publishers for homeschoolers. Inquiry science is the formal name for science that puts questions and thought before answers, and, frankly, it’s hard to find. Worry less about tests, as far too many ask for facts rather than concepts applied to new situations, and scientific thinking is a process, not a series of facts. Yes, facts are important, but divorced from doing science, they don’t create scientific thinkers. Look for questions higher up Bloom’s taxonomy, where questions require application of facts, analysis, evaluation, and creation.

Hands-on experiences that do more than show a taught concept are crucial to teaching the observational skills and thought processes necessary for developing strong scientific thinking. After-the-lesson demos may strengthen fact retention but they don’t stimulate the “why” brain as well that the same demo before the lesson. At least some of the labs and hands-on opportunities should require the learner to design the experiment, ideally formulating the question from observations they’ve already made. It’s fine if not all do. There is plenty to learn from cookbook labs, including technique and the range of possibilities of how to answer a question.

Many lab manuals and texts don’t have this focus, either because of the classroom logistical issues when children ask questions and figure out a way to search for answer (for standard curriculum) or parental ease (homeschoolers are often looking for ease of delivery, understandably). If your favorite option doesn’t do this, alter the experiments a bit. Instead of passing the lab worksheet to your child, read it over and think. What’s the question the lab asks? If I give my child that question and the materials in the lab (plus a few — be creative) without the instructions but with plenty of time and some guidance, could my child find a way to answer the question? (In a later post, I’ll give some guidance on altering labs to be more student-driven and aimed at developing scientific thought.)

Even if your curriculum is full of cookbook labs that you’re uncertain of how to alter, don’t despair. Just ask questions not answered by the text directly. Don’t be afraid to ask the ones you don’t know the answers to, and don’t worry about settling on a single answer. You’re better off wondering and wandering to more sources to search for more answers. After all, a good amount of scientific work is research in response to a scientist’s questions. Again, refer to Bloom’s Taxonomy. Model asking questions that apply, evaluate, and analyze rather than simply require remembering and understanding. Your children will soon do the same.

Here’s a short list of options to consider. It’s not exhaustive. All assume parental involvement. (I’ve not looked for early learner science curriculum in many years.)

  • Building Foundations for Scientific Learning (Bernard Nebel, PhD): Written for parents and educators, these books are designed for non-educators with little science background guiding learners in pre-high school science. Suggested materials are inexpensive and easy to find. This is NOT a workbook or text but rather a source for the instructor.
  • Middle School Chemistry (American Chemical Society): While designed for schools, this curriculum is an easy-to-use, sound introduction to the fundamentals of chemistry for young learners. The materials are easily obtained, and the lessons are clear for both learner and teacher. Here’s my review and materials list.
  • Biology Inquiries (Martin Shields): A full complement of inquiry-based biology labs for middle and high schoolers with clear directions for the instructor and plenty of questions for the students. The materials are generally available through Home Science Tools and your local drug store. (I teach out of this book when I teach Quarks and Quirks Biology.)
  • Exploring the Way Life Works (Hoagland, Dodson, Hauck): This is a text, but it’s the friendly type. This is the text for my Quarks and Quirks Biology course, used along side Campbell’s traditional Concepts and Connections to fill in some details. You’ll not find any fill-in-the-blank questions at the end of each chapter of this thematically arranged book that moves, in each chapter, from the very small to the very large.
  • CPO Science: CPO’s labs offer some fine opportunity for inquiry learning, and the texts are clear and easy to use. However, they often require specialized lab materials. The science-comfortable homeschooling parent can often improvise, but this may be a barrier to some. It’s worth a look on their student pages, however, at the student record sheets for examples of how questions about observations can lead to deeper thinking. (Here’s my review of CPO Middle School Earth Science. I’ve used Foundations in Physics and Middle School Physical Science as well, and find them all similar in style and strong in content.)
  • Just about any curriculum you like to use, with some modifications: Inquiry can happen alone but it’s fostered by community, even if that is just parent and child at the kitchen table or in the backyard. Take the curriculum you’re using now and read through it ahead of your child. Before your child reads, ask questions about what your child thinks now, or perhaps ponder together how something might work. Search online for a demonstration that will encourage thinking before the informational part of a lesson. Ask questions that reach beyond remembering and understanding. Yes, this is harder than presenting the book and some paper for answers or simply doing the labs as given, but scientific thinking isn’t fostered by multiple choice and fill-in-the blanks. It takes conversation.

There’s more to learning science and scientific thought than curriculum, and even a terrific inquiry-based curriculum only the starts the gears of the young scientific mind. My next post will discuss other tools for teaching scientific thinking that you just might want to include in your science learning at home. While you’re waiting, go outside. Watch the ants or the clouds (and see where the ants go when the clouds come). Ask questions. Look for answers. Science is everywhere.




Follow the Ant (Science and Scientific Thinking)

This is the first of two pieces on skills needed to function well in a complicated world. This time, I’ll explore science and scientific thinking.  I’ll list and discuss some resources for encouraging scientific learning and thought in a short post to follow. After that, I’ll explore critical thinking. As always comments are welcome, especially the good resources kind. For the introductory post, read Essential Skills for a Modern World.

Science. Let’s start with what science is not. Science is not the sum of memorized facts about DNA, Avogadro’s number, Darwin’s Theory of Evolution, electron orbitals, the gravitational constant, and tectonic plate movements. It’s not equation-spouting, not those about projectile motion or glycolysis.  It’s certainly not about memorizing who did what when, taking the worst of some history classes to a subject that already is viewed by some to be hard. Science (and math) are too often feared from an early age and far too often taught to young children by people who learned to fear them when they were young.

Science is asking questions about the natural world, musing about answers, carefully and thoughtfully considering what scientists in the field have found before, experimenting as exploration and/or confirmation, and then asking more questions. Children do much of this naturally, watching the world and acting upon it, our carefully timed commentary providing a factual base with context. We name flowers and the birds as our children wonder at them. We explain the tides, the rain, the stars, and the bruise on the knee.

Unless we don’t know. Then, if we’re not distracted by what’s for dinner tonight or whose socks are on the floor again, we look it up — we do research. Better yet, we include the questioning child in the looking up process, or perhaps we pass the job to them. “Hmm. You could research that,” became my phrase as my children’s questions outpaced my answers and library (and before Google was such a dear friend). It didn’t take long before my prompt was unnecessary. “I’ll look that up,” became a usual child-offered solution to his curiosity.

Often, once their question is answered, the exploration is done. But sometimes the questions keep coming. Then, if we’re brave and unafraid of messes and more unanswered questions that will follow, there are experiments. Kids experiment naturally, often asking the next question after repeating an experiment a number of times. (Water and dirt make mud. What happens with water and sand? What happens if I let the mixture dry overnight?) Many science curricula squash this question-experiment-question cycle by providing only experiments (or, more appropriately, demonstrations done by kids) that have answers provided. These cookbook-style experiments are easy on those teaching and have predictable “correct” answers while teaching children what we don’t want them to learn about science: When you enter an experiment, you should know how it will end.

Scientists don’t do it that way. Scientists overflow with curiosity, the sort that takes them to the internet, the library, their bookshelves, the scientist down the hall, and, eventually, to the laboratory. No one source gives them the question or the route to answering it. Relying upon their own experience and the procedures and findings of those who came before, they formulate both the question and experiments, perhaps expecting a particular outcome but never wed to finding it, lest they see what isn’t there or guide the experiment to give the desired answer. And often, quite often, the results aren’t what they hoped or expected, leading to more questions, more experiments, and more research.

“But my child isn’t going to be a scientist. Why does this sort of science education matter?”

DSC00031It matters because, whatever line of work our children pursue, science permeates their modern world. Climate change. Nuclear reactors and bombs. Gene therapy. Stem cells. Invasive species. Missions to Mars. Ebola, TB, and malaria. Alternative energy sources. Water contaminants. If we are to be responsible citizens in this complex world, lobbying and voting for or against legislation on all those issues and more, we need to understand a good deal of science as well as how science works. We can’t vote on what we don’t understand, and we can’t simply vote against something that scares us or will increase our taxes or personal expenses. We need some understanding of the way our universe works to even read about the risks of radiation leaks from nuclear power plants, and we almost always need to research more before we go out and vote on laws.

If we want our children to be able to make responsible and safe personal (and, eventually, family) health decisions, they must be able to read the latest article on gluten or vaccinations or DNA testing and hold up the latest article to careful scrutiny. Junk science and junk reporting abound, especially in health and medical science. In an era where prescription drugs are advertised on TV and pseudoscience, especially about health, fills the internet, we need more than ever to think like a scientist. How many people were in that study? What was the control? Was it double-blinded? Were the researchers funded by Company X, Y, or Z, who just happen to produce or sell drug A, supplement B, or treatment C? Has the study been replicated by someone else somewhere else? Are the results statistically meaningful and practically meaningful?  What questions does this piece of reporting raise? Where can I find out more?

“But I don’t know that much science! How can I teach my kids when I don’t know a beta particle from a leukocyte and couldn’t tell you what’s going on when I take a breath anymore than explain why a bowling ball and a marble, when dropped from the same height, hit the ground at the same time.” 


Start the way your children started. Look at the natural world with new eyes, seeing the ant on your deck as a subject of study rather than occasion for a call to a pest management company. Find the moon every evening, noticing where it is at the same time each night. Watch bread rise and eggs cook.

Then, ask questions. Why does the ant follow the path it does? Where does the ant live, and what does it eat? When does the moon vanish from sight, and just where in the sky is it when it does? Why does it change shape, at least to our eyes?  What’s in those bubbles in my bread, and why do egg whites turn white and firm when cooked?

Next, look for answers about what interests you most. Research the phases of the moon. Read a book about the science of cooking for answers about egg whites, rising bread, and more.  Use reputable sources (applying your critical thinking skills, to be discussed in a future next post), eschewing the junk science and poor reporting found in books, internet sources, articles, and, too often, those around us who also aren’t sure about science. (Charlatans and the simply not scientific abound.)  Be persistent, especially about what is new. Science has a working edge, and it’s at this edge that most mistakes (and poor science reporting) seem to occur. But even old ideas can be wrong or in need of tweaking, so follow the years of research and debate as you read and explore. The way our universe works doesn’t change, but our understanding of it certainly does.

And follow the ant. Watch her (and it is almost definitely a ‘her’), seeing where she goes and whom she meets. Even if she joins a throng of fellow ants, watch your ant as best you can. Does she lead, follow, or neither? Why do you think this behavior occurs? How does she interact with the other ants around her, and what happens after interactions?

Then feed the ant. Set out, on a small index card, a smudge of jelly and place it near the ants.  A few inches away, place another card with chicken or a bit of egg yolk, perhaps, something filled with protein and fat rather than sugar. You pick, as it’s your experiment, but pick with reason and logic. Then sit and watch. Watch longer than you think you can, returning at regular intervals if you must look away. See what happens. What do these ants like? What do they do with the food? How do they find it? Do all of them go for it, or only some?

When the sun sets and the ants return to their home, think. Ask more questions. Consider more ways to find answers. Find a fantastic book or reliable website on ants (see below), and read what interests you. There’s no test, no final paper for which to study. There is only a world to watch and explore and research to read and ponder as you explore the natural world through the lens of scientific exploration and thought.

Ant Resources:



How Does Your Homeschool Bloom?

The new Bloom Taxonomy, with skills gaining complexity as you move up the triangle.

Bloom’s Taxonomy.  Perhaps that’s a familiar pair of words.  Perhaps not.  In short, Bloom’s Taxonomy is an ordered list of six learning objectives designed by a committee of educators in 1956.  Benjamin Bloom headed that committee, so the name went to him over time.  Sounds like a homeschooler’s nightmare.  Committee of educators?  Many of us removed children from school to avoid having our children educated by committee.  1956?  Wasn’t that when rote memorization and corporal punishment reigned?  What use is that to me, a homeschooling parent?

Plenty.  Consider for a moment what learning means to you.  What do you want for your children’s education?  Few of us would say they simply want their children to remember numerous facts, since we’re aware the knowing times tables, spelling rules, the dates of rule for England through the last 300 years, and the genus and species of the ant on the kitchen floor.  No problem with knowing those things.  The first two are tools that can make learning a bit more easy.  The last two are perhaps, at best, lessons in rote memorization, which is a skill as well, handy in medical school and when gathering edible mushrooms.

Bloom’s Taxonomy reminds one that remembering is only the base of learning.  When we ask one to locate the parts of a snail or name the states and capitals, we’re working at the bottom of the pyramid.  Classical education gives four years to honing this skill in the so-called grammar stage, from grades 1 through 4, capitalizing on the sponge-like minds of our youngest kids. Montessori takes advantage of this skill as young as three, emphasizing geography and science at that young age with great success and interest.  For some folks, especially when their interest is piqued, this love of knowledge acquisition never end.

Understanding is the second stage, where one classifies material by any number of criteria, grouping and regrouping.  “Why?” is the question by which we often understanding.  Why does the rain fall from the clouds?  Why did the Civil War begin?  Summarizing and narration, popular activities in many homeschooling methods, fits well into this stage, since it goes beyond simple fact and asks one to restate just what is important into his or her own words.  For classical homeschooling, this takes place in the logic stage, grades 5 through 8.  (Three year olds may take the prize for frequency of asking why, although not all kids really care about the answer until years later.)

For too many homeschool curricula, especially math, history, science, and language arts for the pre-high school set, this is as far as evaluation of learning goes.  Most fill in the blank, short answer, and multiple choice tests require little more than these skills, although at late high school level and beyond, more may be required.  Many workbooks and tests in homeschooling resources stop here for the younger 2/3 of children, only asking them to remember and understand.   It’s not enough.

This is where good use of Bloom’s Taxonomy allows educators, homeschoolers and teachers and alike, to make learning really happen.   The third level, applying, asks one to take that remembered, understood information and use it.  This may mean making a model of a watershed or writing an example of a declarative sentence starting with an appositive and containing a prepositional phrase.  Problem solving utilizing previously learned math rules, such as finding the area of a floor plan, fall into this arena.  This is where knowledge starts to be manipulated and used.

Analyzing takes another jump in thought, and at the fourth level, the learner needs to manipulate information in new ways.  Here, comparing and contrasting activities fit.  What might have been, what could happen later, and discussing what problems occurred are all tasks of this level of thinking.  Knowledge from multiple domains is manipulated, shaped and reshaped, and understanding of a bigger picture occurs.

At the fifth level, evaluating, requires the ability to judge material and create an argument to support one’s thesis.  The thesis could literature based (Which character in Huckleberry Finn shows the greatest growth?), historical (Who was more responsible for the Cold War, the US or USSR?  Defend your answer.), scientific (Critique Pasteur’s use of the scientific method.), or any mix of domains.  Classical education’s final stage, the rhetoric stage, focuses on these very skills.  Certainly success in college and beyond demands ability at this level of the taxonomy.

The sixth level, or top of the pyramid, is creating.  Somehow, creating seems more valued in the traditional second grade classroom (I recall having to draw and write about an invention at age 7.) but isn’t emphasized later on.  Science calls for creating and idea generation by its nature.  Ask a question, devise an experiment, draw conclusions, judge what should come text.  Inventing something (a machine, a methodology, even a taxonomy) or improving upon an existing one fall under this tip of the pyramid.

Of course to apply, analyze, evaluate, and create, plenty of understanding and knowing must exist.  But if a seven-year old (or far younger) can invent and create, surely these needn’t be done in order.  Newer science curriculum, which is often inquiry based (Quite simply, see a demonstration or model, ask questions, make inferences, then get all the vocabulary.) starts higher up the pyramid, even backwards, some may say,  yet the understanding that can come from inquiry based learning is impressive.

Is it more work to hold the discussions, grade the papers, and create and score the tests that come with the higher levels of thinking?  Absolutely.  Do many homeschool curricula approach the elementary and middle school years this way?  Absolutely not.  Should this change?  Absolutely.

The jobs our children will hold as adults will likely require them to create new things and ideas, to judge what is a better or worse choice, to compare options, and to apply knowledge to new situations.  Whether they end up in medicine, law, engineering, education, or in the music studio over their garage, they need the same tools.  Let’s not educate our kids on the first two steps of the pyramid.  Let’s start early, asking them to create, evaluate, analyze, and use their knowledge.


A Very Incomplete List of Curricula Using Bloom’s Taxonomy

Michael Clay Thompson (notably the grammar recipes in the Magic Lens loops but examples exist throughout)

Suppose the Wolf Were and Octopus (questions aligned with the taxonomy, with books for kindergarten and beyond)

CPO Science (Very usable at home and inquiry based.)

Singapore Science (While the content for the elementary texts seems scant by American standards, these teach real scientific thinking quite well.)

Middle School Chemistry (Excellent inquiry science)

Singapore Math (All those Challenging Word Problem texts are great application of skills.  I’ve seen nothing better for the elementary set.)

Art of Problem Solving (Fantastic curriculum for highly talented and driven math students.  Pre-algebra debuts in August.)


Calculus for Young People (Discovery-based math for those in early elementary through adulthood.  Don’t be scared by the title.)

Online G3 (History, Literature, Grammar and more, G3 offers classes for highly and profoundly gifted kids.  Most class time for literature and history is spent on the top 4 levels of the taxonomy.)

Review: Middle School Chemistry

Middle School Chemistry from the American Chemical Society is my favorite homeschooling find of the year for the 2010/11 school year.  It’s their free offering to schools and individuals, and it is science education at its best.  After a rather ho-hum run through Real Science 4 Kids Chemistry I (which I reviewed here), my younger and I were looking for more chemistry to learn.  He wanted plenty of hands-on time but without the dangerous chemicals (sulphuric acid, hydrochloric acid, and other nasties) the older boys were using for their high school chemistry class.  I was in agreement and actively searching for the next step when the ACS Middle School Chemistry curriculum appeared on an email list.

Middle School Chemistry is inquiry based science, meaning that rather than starting a lesson with terms and definitions, each lesson starts with questions.  Generally, a demonstration follows that leads to further thinking on the concept, which is followed by an experiment, sometimes requiring the child to make decisions on the design.  In the second lesson, a discussion of variables and controls provides language for experiment design.  Additional experimental design guidance appear throughout the following chapters.   Terms and concepts are discussed after demonstrations and experiments.  Nothing is taught out of context.  For every concept, the student has watched the result of the concept and experimented with the process.  Thus a student has working knowledge of the concept even before it has a name.  This is not, “Oh, look at that!” science.  Rather this is, “So that’s how that works!” science.

That’s the idea of inquiry learning.  What does it look like in practice?  Chapter 2.3 focuses on condensation.  By this point, the student understands that molecules are in motion and that increasing heat increases molecular motion.  They’ve experimented with these principles and watched brief animations of simple diagrams of molecules in motion.  In the lesson on state changes (going from solid, to liquid, to gas and the reverse), the student first watches the state change occurs in an experiment demonstration.  In this lesson, a glass of ice water left on the counter is compared with a glass of ice water enclosed in a plastic bag with much of the air pushed out.  The student can observe the higher level of moisture on the outside of the glass exposed to the air and can surmise that water came from the air.  Simple stuff, right?

But the focus of the unit is molecular movement and energy transfer.  As the water molecules in the gaseous state lose energy to the cold glass (heat transfer/energy transfer), they move to the liquid state.  Often the movement of molecules is left until higher level chemistry.  So while a younger child may memorize the order of the state changes, the idea that the varying speed of the molecules (and more) is what determines a solid, liquid, or gas, is often omitted.  But not in Middle School Chemistry.  In this lesson, condensation examples are elicited from the students and discussed.  The process is observed as well.  After discussing experimental design, the student does an experiment to determine what temperature conditions accelerate condensation.  Online short animations model the molecular motion at each stage, and knowledge can be extended to water purification experiments and exploration of other factors that influence that state change of water. Plenty of questions for the student to answer on paper or aloud as the lesson proceeds gives sufficient opportunity to process and retain the new information.  Since each lesson builds on the one before, older information is continually used and expanded beyond.

This isn’t science as it is usually taught.  It’s certainly not science as I learned it in school.  The National Research Council defines inquiry science this way:

Scientific Inquiry refers to the diverse ways in which scientists study the natural world and propose explanations based on the evidence derived from their work. Inquiry also refers to the activities of students in which they develop knowledge and understanding of scientific ideas, as well as an understanding of how scientists study the natural world. (From Doing Science:  The Processes of Scientific Inquiry — this link takes you to an NIH curriculum supplement on Inquiry Science for grades 6 – 8.  I’ll review those supplements later.)

This isn’t science as recommended as by The Well Trained Mind and other classical education models.  And it’s not the process of teaching science used by any homeschool science programs I’ve found (although Nebel offers a fine elementary curriculum for grade K-5).  Singapore Science does contain some inquiry, but the labs are somewhat challenging for homeschoolers.  ACS’s Middle School Chemistry is chemistry taught from the roots up, with molecular motion and activity at the core.  It’s by far the best accessible chemistry program I’ve seen for elementary or middle schoolers.  And it’s free.

All the materials can be printed or read from their online side or downloaded to any device that reads PDF files.  I print out the student pages (4 to 7 pages per lesson) and teach from the book on my iPad.  Alas, the demos aren’t viewable on the iPad, so we head to the Mac or PC laptop for that.  There are also 6 to 10 pages of printable text for the child for each of the six chapters, which I’ve assigned my son to read at the end of the chapter.  These short, illustrated chapters are fine summaries of the material learned and supplement the lessons nicely, and they are designed to do just that — summarize what has been learned during the inquiry and discovery lesson.  This is a teacher/parent intensive program (meaning you can’t just hand it to your child and let them plug away — discussion is part of the game), but preparation is minimal.  Most importantly, my nine-year-old is learning chemistry in a deep, meaningful way.  He’s learning to design an experiment to answer his own questions, complete with correctly identified variables and controls.  He’s learning a number of lab skills at an early age.

I’d recommend the American Chemical Society’s Middle School Chemistry to anyone with a later elementary or middle-school aged child who is willing to walk together with their child through chemistry.  I’d guess plenty of parents can learn quite a bit about matter and how the molecular world works, and this program makes it fun.  While it’s written for the 6th though 8th grade crew, it could definitely be used younger with a quick learner interested in science.  It’s suitable for co-op use.  There is a small amount of math involved in the course, but comfort with fractions and decimals (needed when figuring densities) is sufficient.  There is sufficient material to spread the course over a year, as one might in a co-op setting, although we preferred to devour it more quickly (“Can we do Chemistry, Mom? Please!”).

Middle School Chemistry from ACS uses simple, safe, and easily obtainable materials.  While these lists may seem long, you probably have many of the ordinary materials on the second list on hand.  All the materials on the not-so-ordinary list can be used for later chemistry studies.

Not-so-ordinary materials (beyond items found at craft stores and grocery stores)

Ordinary materials:

  • Styrofoam cups
  • Isopropyl alcohol, 70%
  • Clear plastic cups
  • Styrofoam balls, 1″ (4)  and 1.5″ (2)
  • Salt
  • Sugar
  • Epsom salts
  • Mineral oil
  • M&Ms
  • Food coloring
  • Corn Syrup
  • Club Soda
  • Pipe Cleaners
  • Cornstarch
  • Talcum powder
  • Instant hot packs (2)
  • Instant cold packs (2)
  • MSG (Accent flavoring is MSG.  It’s available at Asian groceries under other names.)
  • Baking Soda (sodium bicarbonate)
  • Tea light candles
  • Vinegar
  • Alka-seltzer
  • Household ammonia
  • Hydrogen Peroxide, 3%
  • Glow sticks (2)
  • Cream of Tartar
  • Tincture of Iodine
  • Cornstarch
  • Vinegar
  • Popsicle sticks
  • Citric acid (try the canning section of the grocery store or a natural food store)
  • Balloons
  • Toothpicks
  • Quart-sized ziploc style bags