I decided to try population models with my second year algebra class. Those students also had a really positive reaction. I thought that STELLA would make the structure of a math problem, in this case population growth, clear for them and that’s exactly what happened.

Those experiences gave me the incentive to learn and do more. The software got me interested and then I started learning more about system dynamics.

How did you go about learning more?

Diana:  Nancy Roberts’ book Introduction to Computer Simulations: A System Dynamics Modeling Approach got me off the ground and I learned from several leaders in the fields of Systems Thinking and system dynamics. I saw Barry Richmond speak at a K-12 conference in Tuscon. He was very inspirational. I was lucky to be in one of the groups of K-12 teachers that George Richardson, a consummate system dynamics teacher, was working with. I started writing lessons for my classes. I really liked Nancy Roberts’ book but I couldn’t teach from it.

Is that why you decided to write a book, to provide a resource that instructors could “teach from"?

Diana:  At first I just wanted to write enough lessons to keep the students in both my algebra and modeling classes engaged in building small STELLA models to replicate the types of behavior over time scenarios we were already studying. The use of system dynamics modeling fits hand-in-glove with most of the mathematics we want students to learn at the high school level. As I started to learn more about system dynamics, my lessons started to include feedback analysis and other components of the system dynamics modeling method.

In 1993, I received a National Science Foundation (NSF) grant to train high school math, science, and social studies teachers in modeling. I directed the grant and training, kept teaching modeling in the Portland, Oregon inner city high school where I was co-director of the Systems Program, and wrote even more lessons. My classes grew and the lesson writing continued. That led to a second NSF grant that included more training and still more lesson writing. The core group of teachers involved in the NSF training shared lessons which helped accelerate everyone’s understanding of Systems Thinking and system dynamics.

Someone suggested that I write a book and it seemed like a good idea for a few reasons. Most teachers just don’t have the time to write their own lessons and that would get in the way of inspiring systems modeling education. We also wanted the lesson structure to promote Systems Thinking as well as teach modeling. The lessons for traditional equation-based math classes were different than for modeling classes. We wanted that to be clear. Without Steve Peterson, who critiqued the first edition of the book, I would not have felt confident releasing these lessons for publication.

Was the book immediately successful?

Diana:  Well, it was the first of its kind, there was no competitor! It was written for high school teachers but it caught the attention of business professionals and academics that want to teach themselves to use modeling in their classes or work. Since the book included a set of lessons and models, offered answers, and gave permission to re-use the lessons it was seen as a great investment.

What led you to the second and then third editions?

Diana:  I always send my book drafts to Jay Forrester to get his opinion. Debra Lyneis, who worked with K – 12 teachers to apply system dynamics to the classroom, really enhanced the books with her recommendations. Their suggestions, feedback from students, and my own classroom experience led to the second and third editions.

It’s been important to get beyond the software, which is what gets people excited, to lessons that help students understand a problem, how the problem’s system behaves, how we can change the system, and how to look for unintended consequences.

Again, equations are too abstract to do all those things. They force us to oversimplify and strip out the interesting parts of problems. Together, Systems Thinking and STELLA give students a way to visualize all parts of a problem. I had a student that was able to explore the problem of why there weren’t enough hybrid cars available in the market. That student couldn’t have thought about that problem with equations. With lessons on Systems Thinking and modeling and how to use STELLA, he could.

What does the third edition add?

Diana:  The third edition really completes the book. It includes most of the important concepts that are needed to teach a comprehensive high school course in systems modeling. Besides adding an "Introduction to Oscillations", it includes additional lessons on feedback loops like "Explaining a Feedback Loop" and "Transfer of Loop Dominance". There were concepts I kept re-explaining to students in class and decided they should be in the book!

Specifying units is another thing I always have to talk about with students. It can be hard to keep units consistent in a large model and so I added a lesson that shows them how to use the software to check for unit consistency.

I learned about starting a model in equilibrium from James Lyneis and now there’s a short lesson on that. Some of the system dynamics classes I took at Worcester Polytechnic Institute reinforced the importance of model testing, so the new "Pollution Model" lesson incorporates significant testing concepts. Barry Richmond always pushed to have students tell the story of their model and a new document helps them use STELLA’s storytelling feature to unfold their model for an audience.

Many of my students said that the lesson in how to prepare to build an original model was extremely helpful to them. A new chapter called "Class Demonstration of a News Article" uses a Newsweek story to guide them through the necessary prep work: identifying the systems involved, focusing on one, specifying variables, determining reference behaviors, and forming a hypothesis. This chapter is designed to help a new modeling teacher follow this process. It explains the process step by step, using an example I have used many times with my students.

With the book complete, what’s next for you?

Diana:  Systems modeling is the most exciting thing I’ve ever learned or taught. I really believe it is essential for the next generation if they are going to be able to tackle the problems they’ll face. As Jay Forrester says, we can’t change mental models or behavior just by providing a logical argument. We have to build models.

We’re not going to get anywhere in teaching systems modeling without K-12 teachers. I want to interest and teach them through workshops. I also want to write professional articles that would support their interest in modeling and provide leverage with administrators and other curriculum and professional development decision-makers involved with K-12 education. We, in K-12 Systems Thinking/system dynamics education, need to back up all our strong anecdotal evidence on the power of systems modeling with data that shows how it provides tools for enhancing the analytical skills we need kids to develop.

Right now I’m a student at Portland State University in the Systems Science department. I want to figure out how to collect the data we need to prove the power of teaching systems modeling to students. We have to present data so that adults will ask, “Why don’t my kids have access to this?”

I’m passionate about teaching systems modeling and I’m willing to devote the rest of my career to it.