scientific method

Becoming a Scientist

It’s how you think.

The gas flame hissed at full height while a pot sat precariously askew on the burner. There, at eye level to the flame and pot stood my little 5-year old son.  He was trying to stabilize the pot with one hand while clutching a partially filled balloon in the grimy damp fingers of his other hand.  Sweat dripped from his temples as he focused intently on his task.  He didn’t even notice me approaching his hazardous situation.

“What are you doing?”

He looks up at me with his big, open, intense blue eyes. Maintaining his grip on pot and balloon he explains, “Trying to figure something out”.  I help him with the pot as he continues; “You know how when you have a balloon in the hot car it pops?  Well, I want to know if that has to do with the heat of the car. “

We study his experimental set-up and he adds, “The balloon should get bigger if I put it in the hot water”

And there it was. The inherent curiosity. The desire to know. The determination to find out. The pursuit of a test. A formed hypothesis. It wasn’t something we taught him. It was just there.

Of course, with my guidance he completed his experiment and jumped with joy when that balloon began to expand.  He loved the idea of air molecules speeding up so fast to take up more space and pushing on the sides of the balloon to make it look like it was “filling up”. 

“If we take it out now, it will shrink again, right?”  Of course, we did it.

It seems his entire childhood was spent in testing the world. As an adult this son continues to think like a scientist, answering everyday life’s questions using the scientific method. He can’t help it. I know, because I’m the same way. 

However, not everyone thinks this way.  I see it all the time in the classroom. One student sits in a stupor while his neighbor has ten great ideas for research questions. Despite learning the proper steps and being shown the way, it still is so much more difficult for some than others.

As science teachers, it is our responsibility to do everything we can to teach the scientific method and use it as the framework for all activities in the lab.  All students can learn to formulate a proper research question, to form a hypothesis, to generate a table of variables, and to carry out an experiment using necessary lab skills.   However, some students will be stronger at thinking up innovative questions and designing creative experiments because their minds think differently than their peers.

The different wiring of brains becomes more and more apparent as students progress into the more advanced classes and are expected to become more and more independent in the design of experiments.  Students really separate out during the internal assessment process in IB science where total independence is required.  Then, there are the students who choose to do their extended essay project in a science, which is an opportunity for them to design and conduct an experiment completely stemming from their own interests, not a small feat.

It is a pleasure to foster the growth of budding scientists but there is something really special about spotting that scientific mind and seeing it wonder and wander through a myriad of questions and possibilities.  It’s true, the best I can offer as a teacher is to teach the students the framework of the scientific method (and content) and to foster the growth and expansion of the mind.  Scientists need the freedom to meander intellectually and be free to test their ideas.  That’s my job, to give those minds that freedom. 

Making Biology Labs Happen

Yesterday after school I biked home, dropped off my bags, and immediately headed to the metro.  It was imperative that I make it to Pet Place before closing time.  I knew where to find the mealworms and found them easily.  After debating between one or two containers, I settled on two.  As I left the pet store I stopped at Blokker and Zena to additionally pick up fertilizer, antifreeze, and patio algae remover.  I couldn’t find a bag of soil before the stores closed so I made a plan to take my own bag from the bike shed, despite it’s large size.

At seven in the morning I haul the 50 kg bag of soil along with the mealworms and chemicals up to my classroom on the 3rd floor.   I set up the chemicals and soil on one side of the lab with an assortment of glassware, beakers, foam cups, stirring rods, and graduated cylinders for the students to select from.  I am glad neither of the labs today requires making solutions or excessive preparations. Opposite the collection of soil and chemicals, on another lab bench,  I place the mealworms next to a box of corn flakes.  Colleagues passing through are often disgusted by the experimental contents in my classroom and the mealworms are no exception.  “I could never do Biology” is often the phrase I hear, “It’s just so gross”.   

The IB Environmental Systems and Societies (ESS) students tackle their lab by initially formulating their research question (How does plant fertilizer affect the height of wheat plants), hypothesis, and table of variables.  Next they outline their procedure and begin weighing out soil, counting wheat seeds, and preparing solutions with varying percentages of fertilizer.  They discuss the best method to calculate concentration of fertilizer, they debate the planting technique, and trouble shoot a method to allow drainage of water.  They analyze each step of their procedure seeking to identify whether there is a controlled variable they need to add their list, for example, the planting depth.  Finally, they place their carefully prepared experiment under the fluorescent lights.

Meanwhile (yes, these classes meet together) the IB Biology students read through their “Transfer of energy lab” procedure and immediately a ripple of “Eww”s  is heard. I hold up the containers of wriggling creatures and the  students crinkle their faces, “Do we have to touch them?”  Facing the inevitable, however, they are eventually overcome with curiosity and begin sorting their worms and weighing out the corn flakes.  Their i-phones, of course, document the entire procedure. Once the lab is set up, the students plead to be allowed to feed the turtle a mealworm.  The entire class crowds around the turtle tank with i-phones in position and a worm is dropped into the tank.  It’s as though they’re watching fire works: exclamations erupt as the turtle ingests the worm, then spits it out, and ingests it again.  After that excitement, the students settle down with the last few minutes of class to start writing up the experiment.

I delight in the experimental aspect of all my courses, as it is during those times that true wonder and discovery envelop the students.  It is when they actually grasp the scientific method and develop analytical skills.  It is worth all the unconventional things I need to find and bring into the school.  Indeed, being a Biology teacher does have its quirky side but I wouldn’t trade it for any other job!  How about you, what unusual aspect of your job do you enjoy?

Teaching the Scientific Method

Sometimes I wonder what is being taught in science classes around the world.  Each year we receive transfer students in every grade arriving from nearly every continent on earth.  I teach 6th, 8th, 9th, 10th, 11th, and 12th grade Science thus, I have contact with practically every secondary student in our school.  My colleague and I took the IB lab report rubric for internal assessments and reduced the requirements gradually for each grade level down to 6th grade.  Thus, students attending our school from 6th grade on will have solid preparation in the scientific method and in lab reports by the time they enter the IB program.

For an overview of the expectations at our school, students entering 6th grade are expected to have a basic understanding of what it means to perform a “fair test” in science and to properly graph the results.  Some have an understanding of hypothesis.  By the December of 6th grade students are expected to be able to construct a research question in the “How does [independent variable] affect [dependent variable]?” format, to form a hypothesis in the “If [independent variable] affects [dependent variable] then increasing/decreasing [independent variable] will increase/decrease [dependent variable]”, and to identify the variables (independent, dependent and controlled with units).  Furthermore, they learn to put together a proper research report including the materials, procedure, raw data, processed data, graph, results, and conclusion.  They are introduced to designing experiments.  In 7th grade they are expected to create their graph in Excel and provide at least one weakness with suggested improvement regarding the experiment.  Their designs should include five values of the independent variables with three trials.  In 8th grade they need to include a trend line and at least three weaknesses with improvements.  In 9th and 10th grade they are practically completing IB quality labs as they add error bars to their graphs, descriptions of their calculations, and a thorough conclusion and evaluation.

So, when I get new middle school students who can’t follow any aspect of the scientific method I am perplexed.  When I get a transfer high school student who doesn’t know how to formulate a research question or identify variables, I am stunned.  How can a middle or high school student never have been exposed to writing a research report? In my opinion every scientific investigation should be framed by the scientific method.  In middle and early high school students should be immersed in the process in nearly every science class.  Gone are the days of lectures.  The science classroom should be a place of regular scientific discovery in the context of the scientific method.