How does smell travel? – Reflections

Why is this science?

Using several forms of representation—drawings, animation, computational simulation—the students have ideas and questions about the mechanisms by which odors travel from their source to someone’s nose. Do smells move everywhere on their own, or do they move because someone breathes in? What are smells made of? Does the act of smelling consume the pieces of odor?  They consider answers to these questions, using the representations both to communicate ideas and, for the simulation, as a runnable model of how smell might work.

As they focus more on the simulation, and on developing it as a model, they work to check it for (1) consistency with their experience, for example that smell is more intense when you are close to the source, and (2) mechanistic plausibility, for example that some piece of smell must enter the nose and be consumed.  In these ways, throughout four sessions of activity, the students are working toward understanding how smell works.  

What contributed?

There were several contributions to the group’s sustained engagement in exploring smell.

Students’ rich experiences with smell
They drew on many aspects of their experiences of smell, from how oranges smell more strongly if they are peeled to how certain substances like barbeque sauce are more “pungent” than others to how smells diminish with distance. This knowledge helped them have and assess their ideas about how smell travels, as well as to see their roles as creators of understanding.   

The media for drawing, animating, and programming 
All of the activity centered on the students’ drawings, stop-motion animations, and computer models, with evident consequences for their thinking.  Their initial drawings raised questions of how smell moves.  Their stop-motion animations led them to ask “what is smell made of?” and to consider that smell is comprised of individual particles, which they called “oogtoms.” Their computational model in StageCast Creator highlighted a need to understand how smell “fans out” from the orange, leading them to consider the concentration of smell particles and what happens when they come in contact with a smeller. 

By design, the students began with the familiar—pens and paper—and progressed to their learning new tools. After drawing, they learned stop-action animation, which builds on the familiar act of taking pictures of creations with everyday materials. Finally, they had their first experiences with computer programming. This progression seems significant to their sustained activity: The new tools had their own appeal, and they engendered new thinking about smell.    

Throughout the activities, the students and facilitators approached the work with humor, both on the side of the work and within it. For example, thinking of a word for what smell is made of, the students had been thinking they should use a science work like atoms. A facilitator offered a silly sounding word from German, “dinksbumps,” which drew laughter, and the students came up with another playful word, “oogies,” which they ultimately joined in a portmanteau with atoms:  oogtoms. Simply put, they were enjoying themselves.

Facilitators’ support
This took place as part of a research project, which afforded three active facilitators working with the four students. They played strong roles throughout:

  • highlighting aspects of what they girls said and represented in media, such as noting similarities and differences between drawings;
  • encouraging the students to give names to their ideas;
  • embracing and contributing to playfulness, including in those names; 
  • and scaffolding the computational modeling, by encouraging the students to think about how smell moved one step at a time, and by programming in features that were more complex, such as the random motion of the oogtoms.