Mallory Dyer

Mallory Dyer, math professor at Central Arizona College, displays her graphing-calculator app on a smartphone. 

SIGNAL PEAK — Mallory Dyer has a problem. It’s a word problem, the kind she gives students in her math classes.

Dyer, 31, is a math professor at Central Arizona College. The problem goes like this:

“Kenneth plans to attend the Pike County Fair and is trying to decide what would be a better deal. He can pay $35 for unlimited rides, or he can pay $15 for admission plus $1 per ride. If Kenneth goes on a certain number of rides, the two options wind up costing him the same amount. What is that cost?”

My answer would be: You couldn’t pay me to go on half the rides at the Pike County Fair. Not after three corn dogs and a monster shake.

And I would be wrong. Dyer wants something a bit more involved. She adds:

“Write a system of equations, graph them and type the solution.”

She lost me there. But students in her classes are expected to have answers. And those answers call for lines on a graph.

That, in turn, calls for a special calculator, a graphing calculator. But graphing calculators cost as much as $100 and up. For students at a community college, it’s a big purchase. In one of Dyer’s classes, out of 30 students, 20 couldn’t afford a graphing calculator.

“I saw them really struggle,” she said.

She saw the need for something affordable.

Dyer spoke from behind her desk on campus. She had a graphing calculator handy. It looked like a small brick with a screen and a keyboard full of numbers and symbols I didn’t understand.

She held up the calculator, the thing that one out of three students had. Then she held up a smartphone.

“Everybody has one of these,” she said.

In September 2014, she began to think about creating a newer, more affordable graphing calculator. It would use the smartphone everybody had. In March of last year, she began, in earnest, to develop an app that could turn any smartphone into a graphing calculator.

She teamed up with her husband, Josh, a financial software consultant.

No question about it. Dyer is a math wiz. Somebody who knows her way around a linear equation. Somebody who’s always been keen on numbers.

“Math was something I was always into,” she said. “I always took the hardest math classes. I was always doing math puzzles.”

But Dyer’s anything but one dimensional. She grew up on a cattle ranch near Marana. So riding a horse is second nature. She raised cattle for 4-H.

“I showed up at the Pima County Fair every year,” she said.

She arrived at CAC as Mallory Parsons, an 18-year-old freshman. She had a basketball scholarship. She wasn’t tall, about 5-foot-4. But she could dribble and shoot. And in her sophomore year, 2005, CAC’s Vaqueras won the national junior college women’s championship.

Dyer went on to Arizona State University. But she stayed with Vaqueras basketball as an assistant coach. It’s a job she still has — and likes. She’s the one handy with the X’s and O’s.

Here’s another thing about Dyer. She’s engaging, friendly and knows how to market a good thing.

She and Josh have already rolled out the first version of their graphing-calculator app. It’s available now for Android-based phones. The iPhone version is planned for summer.

It runs $4.99 — or about one-twentieth the price of a brick-like calculator.

One download and it’s good for as long as the phone lasts. A student can use it all through college. Or even high school, where higher math has also taken root.

The app’s graphics, Dyer added, are color coded. One line could be red. The other blue.

The app comes with a scientific calculator as well. Most smartphones already have that, Dyer said. Most smartphones also give students the tools to go beyond a mere calculator.

They could, in a pinch, text in search of answers. Or turn to Google. They could, but that would be cheating. Here, the pricey calculator has a leg up. It only calculates. It doesn’t do texting or the Internet.

Dyer thought of that and imbedded an anti-cheating feature in her smartphone app. It’s part of the app’s name: Lockdown Graphing Calculator.

Here, a teacher can enter a code unique to any phone. This allows said teacher to disable all but the calculator app. The smartphone is locked down for a pre-determined time — maybe for two hours during a test.

Dyer and her husband see big potential here, even lockdown outside the classroom.

“Parents can say, ‘Your phone is locked down for two hours, do your homework.’”

And lockdown for other subjects. Chemistry and other sciences. English. Social studies. Everything outside the lesson would be walled off.

To date, the Dyers have sold 230 downloads. CAC has approved it for the classroom. And they’re looking for a bigger launch this summer. That could require more backers and financing.

To get the word out, they’re attending educational and tech conventions.  They have a website:

If the Dyers get it right, classrooms everywhere will have the lockdown app. And students will be focused like a laser on the work at hand. No outside help, except for 911, if really necessary.

I can see it now.

Operator: “What’s your emergency?”

“Calculus. It’s killing me.”


Reach contributing writer Bill Coates at