By Paul F. Lai, PhD Candidate, UC Berkeley Graduate School of Education

By In her fifth year teaching computing, Melissa Dohm found an engaging and effective new way to introduce the core concept of binary to her diverse middle school students at Ochoa Middle School in Hayward, California. She discovered *Secret Coders,* a graphic novel created to teach coding to adolescents.

*Secret Coders*, written by Gene Luen Yang (himself a longtime Bay Area CS teacher) and illustrated by Mike Holmes, premiered its first volume in October 2015. The graphic novel unfolds the story of Hopper and Eni, two intrepid pupils in a Hogwarts-like private school, where instead of mysteries coded in magic spells, the secrets are revealed through fundamental coding concepts.

I spoke with Melissa, also a technology teacher leader and English teacher, about using *Secret Coders* to teach binary.

**Lai**: You had an inventive way to teach binary in the past, is that correct?

**Melissa:** Since my first year, I taught a binary using a “magic trick” in which students learned to guess a number between 1 and 15 by asking a series of questions. Students made an Excel project with conditional statement functions to get the right number. They loved it and would show all their friends. But getting them to “understand” binary was challenging and would take a full week of struggling with the concept.

**Lai**: How did *Secret Coders* help you teach binary?

**Melissa**: The comic was a quick and interesting. When Eni starts to describe binary to Hopper, rather than using strictly mathematical language, he makes it into a game with pennies and boxes drawn with sidewalk chalk. I borrowed that game for our class’s “kickoff,” copying Eni’s methods and replicated those steps from the comic on my board, with magnets and boxes. Kids were really excited by the puzzle, and seemed to easily grasp the concept.

**Lai**: So the graphic novel provided a visual and game-based way of letting students play with how a series of “yes” or “no” configurations.

**Melissa**: And they really grasped it. When I announced, “We’re going to read a comic book today!” the students were thrilled. I gave a synopsis of the main characters and setting as we walked through the beginning pages.

**Lai**: You’re an English teacher as well, and familiar with how comics work. How did the visual narrative of a graphic novel help with conceptual learning?

**Melissa**: The book was a phenomenal addition to the binary lesson; they couldn’t put it down. They responded to binary as part of the mystery of this haunted school. When I asked them whether Hopper had gotten it right the first time, they all knew where she’d gone wrong. What normally took a week for me to teach, most of the students understood within a day.

I usually typically use a presentation to explain the history of binary, the base 2 system, etc. But this time, they received that information much differently after the graphic novel lesson. And they did really well with the activities involving the magnets and boxes on the board. By the time we took the quiz at the end of the week, a much higher proportion of the students— nearly all of them— showed that they understood binary. They even excitedly taught it to another teacher!

**Lai**: Describe your classes.

**Melissa**: Our school is very diverse, so I have students from many ethnic groups, a growing number of girls, kids from different socioeconomic backgrounds, and students with different abilities. One of my female students struggles with basic math concepts, but the magnets, columns of boxes, and visuals from the lesson gave me a way to support her problem-solving when she was otherwise stuck. She couldn’t do the basic math, but Eni’s lessons and the columns helped her figure it out.

**Lai**: How do you plan to build upon this experience?

**Melissa**: The kids are really curious what happens next in *Secret Coders*. They wanted to know how they could get the book so maybe they will read ahead and spoil it. We will try out the next parts of *Secret Coders*, where Hopper and Eni start learning to code with a robot turtle and I plan to use future installments of the graphic novel. Giving students the story and characters to care about, along with the smart visual lessons you can present in something like a comic book, really fits the way I try to teach computers in interesting and hands-on ways.

More information about *Secret Coders*, as well as instructional resources, can be found at *www.secret-coders.com*. Read more stories with ideas for increasing diversity in CS education in the CSTA *Voice. *