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Scratch Explorables

Philippe Put on Flickr

A chance encounter with a virtual tornado recently sparked a new perspective on media and student engagement for me. During a 7th grade meteorology unit, I watched students interact with an explorable computer simulation of the Tornado intensity scale (or Fujita scale). Using a slider, they increased or decreased the environmental conditions and watched as their tornado’s intensity increased from an F0 to an F5. Kids being kids, the exercise was quickly turned into a game with some students attempting to make their tornadoes more powerful while others aimed for F0.

By learning about tornados through interactive play, these students were developing a higher-resolution of understanding than by only reading a book chapter or watching a slideshow. The simulation gave students a sandbox to explore the destructive power of tornados and encouraged many to search out more information and ask more questions. I was amazed at how the simulation held their attention and how playful the exercise turned out to be. This was a good sign. As a rule, I find that whenever I encounter students playing in a school setting, learning is happening behind the scenes.

While writing computer programs to create an instructive simulation is not a new concept, new technologies such as HTML5 have made explorables an emergent new technology in education. In 2011, designer and computer scientist Bret Victor coined the term “explorable explanation” and referred to these instructive tools as a new “dynamic medium”. Interactive models are powerful because they encourage the user to not just consume content, but to play around with multiple variables in a complex system. From anthills to world economies, explorables help students grasp the influence that factors can have on tricky concepts.

While interacting with an explorable creates a strong understanding of a concept for a user, creating an explorable is a different task altogether. This level of making requires a solid understanding of a system and its factors. Being able to translate this understanding into a simulation for others is no simple task, but it is incredibly worthwhile. A class can create a set of explanations that can help explain the concept to next year’s group creating a continuum of play. In fact, I believe that working with data and simulations could possibly merit a new revision to the age-old learning goals in Bloom’s Taxonomy.

The good news for teachers, however, is that a simple tool found in many primary computer science classrooms was designed for such a purpose. Scratch, with its easy access to variables, sliders, and animations, is perfect platform for elementary and middle schools students to build explorables explanations. In fact, Scratch’s predecessor, Squeak, was even designed to allow for such a task.

In my first foray into explorables, I asked a group of motivated 6th grade students to create an explorable that represented their data from a creek health project. Students had already collected data from the creek in the weeks prior. The first step in the Scratch portion of their project was to create variables and sliders for dissolved oxygen, number of invertebrates, and other factors. They thoroughly enjoyed the process of creating varying backdrops and sprites representing the health of their creek. As the sliders were moved and the variables changed, the students programmed their sprites and backdrops to respond accordingly. Figuring out the math and the conditional statements was the most challenging part for the students, but the majority in my group were highly motivated throughout the project.

As we start a new school year, my goal this year is to add more interdisciplinary explorable projects. In my mind, the increase in student engagement and understanding far outweighs the Scratch learning curve required. As students gain more competency in creating simulations, I imagine they could move on to more technical platforms such as Idyll, Processing, or HTML5 by high school. In the end, as teachers, our goal is always to increase student understanding and competency, and explorable explanations are playful projects that help to do just that.

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