Cellphone spectrometer brings invention back to science classrooms

Professor Alexander Scheeline in the Department of Chemistry at the University of Illinois is one of the Senior Personnel on the EnLiST project. Along with a number of colleagues in the Department of Chemistry, he has been pivotal to the development and delivery of the EnLiST Chemistry Summer Institute; a two-week intensive learning experience for EnLiST Fellows who teach high school chemistry. A hallmark of the EnLiST Institutes is the creativity and entrepreneurship that science faculty bring to the task of engaging EnLiST Fellows with learning experiences that are both accessible and cutting-edge, while providing for ways to enable teachers to take such learning experiences back to their students. Professor Scheeline is in no short supply of both creativity and entrepreneurial skills when it comes to working with students and teachers.

Professor Scheeline at the University of Illinois likes to think that science is very similar to music. In explaining the similarity between the two, he presents the analogy of attempting to learn a Bach fugue. When practicing, you get to the point where you are good at playing most of the fugue, except for a select 20 seconds. What do you do? You practice the section that needs work. “You run t

owards the problem,” Scheeline says. “The same thing is true of research and especially in the chemical sciences. Most things you understand. What you want to do is break down the things you don’t understand.” This perspective permeates the way Professor Scheeline approaches teaching. For about 30 years, he has taught spectrometry as a part of the field of analytical chemistry. “I tried for 25 years to teach students the concept of stray light and they could mouth the words, but they had no clue what it was,” says Scheeline.

In May of 2008, Professor Scheeline went to teach a class of students in Hanoi, Vietnam as a result of a collaboration of the Department of Chemistry at the University of Illinois and the Department of Chemistry at the Hanoi University of Science. He was shocked by the squalor he saw; their resource base was thin, aside from a new set of lab benches. While these conditions were not initially a problem for this particular visit as he was teaching quantitative analysis, the next year Professor Scheeline was supposed to return to teach instrumental analysis. “I thought, ‘how in the world am I going to teach instrumental analysis to students who have never had their hands on an instrument?” To Scheeline, the answer seemed obvious: to have the students build a simple instrument in order for them to understand how it works. After deciding on the topic of spectrometry, he set out to find the materials to make a cheap spectrometer. For the light source, he put together a LED light and a three-volt battery, like the ones found in car key fobs for 88 cents apiece. By this time, Kathleen Kelley was an EnLiST teaching assistant, and it was she who figured out the elegant, connector-free battery/LED assembly. In addition, the diffraction gratings and cuvettes necessary are cheap and easy to find.

From there, the only missing component was a cheap photodetector. Fortunately, in this day and age, the problem can be solved easily enough. Scheeline had noticed during his visit to Vietnam that many students had cell phones, and many of those cell phones had cameras. Unique to this undertaking, he also developed software to supplement the spectrometer. “If you don’t have the software, you have this data, which ends up being a bunch of pretty pictures, but what do you do with it?”

While this financially savvy spectrophotometer is not the most accurate instrument, its obvious flaws inspired him. “One of the reasons it’s hard to teach about modern instruments is that while they have all the flaws that old instruments have, it’s hard to see the flaws because they have been reduced to such low levels. Here, that’s not a problem.” It is this failure that allows students to discover concepts and limitations of analytical chemistry and spectrometry for themselves. Scheeline saw this phenomenon when he went to a summer outreach program at Clark Atlanta University in 2009. When a high school student in the program saw the room light affecting the results of the cell phone spectrometer, she realized there was a problem. Due to the fact that the inner workings of the instrument were exposed, rather than the usual design of having a spectrometer enclosed in a box, she discovered the concept of stray light on her own. This use of an instrumental flaw, dubbed a ‘creative failure’ by Scheeline, acts as a teaching tool that forces students to problem solve. Science should be more than simple memorization and regurgitation; it requires creativity. Professor Scheeline put his spectrophotometer toward this very use during the 2009 and 2010 EnLiST Chemistry Summer Institutes.

Scheeline believes that creativity “is one of the things that is missing in American education these days, because if you’re teaching for a multiple choice test, you cannot teach creativity. Here, you say, ‘here are some parts, go play,’ you’re teaching creativity!” In bringing creativity back into the classroom, building the spectrometer themselves can help develop skills required for inventing. Even if the students only create what has already been invented, the thought process of developing ideas is represented.

The importance of this project also extends past the classroom. For instance, the use of cheap instruments in the classroom can act as a leveler to paves the way for a more egalitarian scientific field. “The ideal thing, of course, is to open the pipeline to everybody rather than just the stereotypical upper middle class and the people that have been dominating American science for the past couple of generations,” says Scheeline of his hope for the future of the field. He has already had the opportunity to see how the cell phone spectrometer is a step in the right direction. In getting the word out about this project, Scheeline was contacted by a high school teacher in Camden, New Jersey with limited resources wanting to bring this project to his students. As a direct result, the morale of the teacher had improved along with the self-confidence of the students. By giving students the opportunity to be able to do things themselves, they are affording them the chance to gain a sense of self-efficacy; it becomes something that they can say, ‘I can do this myself.’ In his words, “the first person singular really matters to most people.”

In addition, Professor Scheeline has always been very open with sharing his developments with others and making this particular resource available to science teachers across the nation. From the beginning, he was always open to collaboration and other’s input. In relation to the software that he wrote, he always knew that it would one day become an app for a cell phone. When Dave Bomberg asked about adapting the idea to the Android phone, his response was to go for it. His approach is to “join the crowd, have fun with it.” As for advice for teachers embarking on developing their own projects, he simply says, “Just do it!”