Corrected: An earlier version of this article included inaccurate phrasing regarding the findings from the National Assessment of Educational Progress. Data extracted from NAEP show the percentage of students.
A previous version of this story mischaracterized the initial investments in Desmos. Mitch Kapor and other groups invested more than $800,000 in the company.
There are countless examples of web-based tools challenging the need for hardware devices: VCRs, CD players, and fax machines—all once commonplace—have been relegated to the backs of many closets and garage sale piles.
The same potential threat is now facing a device once considered indispensable to secondary math teachers: the hand-held graphing calculator.
One company in particular is upending the market: Desmos, a San Francisco-based startup, has created a web-based calculator that works across devices and browsers and, perhaps most enticingly, is free for teachers and students. That means schools and parents are starting to think twice before paying between $60 and $175 for the hand-held calculators that have long been a staple in algebra classes.
Proponents of hand-held calculators quickly counter that web-based tools are far from cost-free: In addition to purchasing hardware, such as tablets and laptops, schools need to pay for information-technology support and reliable broadband to use those tools.
Recently, the Smarter Balanced testing group announced that it was embedding the Desmos calculator into its online math assessments—a move that Desmos officials say other major testing companies are considering as well. “The old hand-held devices are sort of entrenched because they’ve been institutionalized in standardized testing and curriculum in a very serious way,” said Doug Ensley, deputy executive director at the Mathematical Association of America. “What Desmos is doing is loosening that grip.”
For now, that grip seems sturdy: Hand-held calculators still have quite a heavy presence in secondary math classrooms. And many teachers say that until the college-entrance exams, mainly the SAT and ACT, make the switch to online calculators, there’s no getting away from practicing with the hand-helds in class.
Desmos has openly made Texas Instruments, the company that’s dominated the K-12 graphing calculator market for nearly 30 years, the target of its disruption efforts.
“It was amazing technology when it came out,” Eli Luberoff, the CEO of Desmos, said of the TI80 calculators, which debuted in 1990. “My beef is it just hasn’t improved in cost or quality or usability since.”
But according to Texas Instruments, the simplicity of the hand-held calculators is part of what makes them a good choice for schools. “We only focus on the pieces students need in classrooms,” said Peter Balyta, the president of Texas Instruments Education Technology. “We do that without the many distractions and test-security concerns that come with a smartphone or tablet and the internet.”
More than 90 percent of high school students using graphing calculators are still using hand-held versions, according to third-party research conducted for Texas Instruments, and that hasn’t changed in the past four years.
According to Balyta, Texas Instruments adds 5 million graphing-calculator users a year. Graphing calculators are a relatively small portfolio item for the Fortune 500 company, which has 30,000 employees and posted $13.37 billion in revenue last year.
Desmos won’t release exact numbers, but Luberoff says it has “millions of active users every month.”
But the small, young team at Desmos is betting teachers and students aren’t wedded to those hand-held graphing tools.
Luberoff conceived of what would become Desmos as an undergraduate at Yale University a decade ago. He was tutoring math students in nearby Westport, Conn., and realized “they were still using this outdated technology that I used and that astonishingly they’re still using today—the TI84,” he said. “I decided to see what browsers could bring to this situation.”
He took a year off from school to work on the software, then returned to major in math and physics in 2009. Two years later, the startup received more than $800,000 investment from Mitch Kapor, an entrepreneur who invests in tech startups aimed at narrowing gaps in access for disadvantaged groups, and several other investment groups.
Luberoff now has a team of 17 designers, coders, and math educators on staff, including Dan Meyer, who became a star in the math education world after his 2010 TED Talk “Math Class Needs a Makeover” went viral. The group also has 80 teacher “fellows,” who are selected through a competitive application process and flown to the Desmos headquarters in San Francisco for training. The fellows test new features in their classrooms and stay in touch with the company to help improve the software. (The fellowship is unpaid, but some participants can end up earning money leading professional-development workshops.)
The Desmos business model is a fairly novel one: The general public can use the online calculator and all its associated features for free. The company charges textbook publishers, such as Pearson and The College Board, to embed its tools.
“Students go into that book and have access to our calculator right inside of it,” said Luberoff. “There’s just a button that opens it. There’s also interactive graphs powered by Desmos” that students can manipulate.
And now the company is making inroads in the assessment world as well. Smarter Balanced, the test aligned to the Common Core State Standards being used in 15 states, including California, will use a secure version of the tool in all its math tests next spring. Smarter Balanced paid $460,000 for a three-year contract with Desmos.
Tony Alpert, the executive director for the Smarter Balanced Assessment Consortium, said the group is moving to Desmos because it’s more accessible for students who are blind or visually impaired than hand-held devices. A joint press release from the groups also pointed to the $100 price tag for hand-held calculators as a reason for the switch.
Luberoff says his company is “in discussions” with organizations that provide other major tests as well, including the SAT, ACT, and the Partnership for Assessment of Readiness for College and Careers. “We talk with everyone,” he said.
Some warn, though, that it’s misleading to say Desmos is free for schools. “When you look at the cost of hardware like tablets, IT infrastructure, and device management, I don’t consider it free,” said Balyta of TI. “Those costs really add up.”
With state testing now being administered online and more curricula going digital, schools are being asked to make those investments anyway. But that doesn’t mean the technology is always working when classroom teachers need it.
“Right now in our school, Wi-Fi is a big bottleneck,” said Samuel Williams, a mathematics teacher at Curtis High School in New York City. Around lunchtime, “I can’t even check the internet. Relying on an app that needs connectivity—you’re out of luck.”
Once Desmos has been downloaded, many of its features can actually be used offline. Meyer, who works as the company’s chief academic officer, says that can help solve the in-class distraction and potential cheating problems as well. “Airplane mode and having your phone flat on the desk—that’s probably what I’d be doing if I were in the classroom right now,” he said.
For their part, TI representatives say there’s still plenty of classroom interest in the hand-helds. “If you’re asking do we feel that online apps have had an impact on our graphing calculators, I’d say no,” said TI’s Balyta. “They’re being used at the same levels they have been for years.”
Among tech-savvy middle and high school math teachers, there’s undeniable enthusiasm around what Desmos is trying to do.
At a recent math conference in San Antonio—ironically, one with a prominent sponsorship from Texas Instruments—hundreds of educators packed the ballroom for a morning keynote speech by Luberoff on increasing equity through technology.
Twitter and the K-12 math blogosphere are full of examples of teachers showing off their students’ Desmos graphs and proclaiming their love for the tool.
Kristen Fouss, who teaches Integrated Math 3 and precalculus at Anderson High School in Cincinnati, is among the loyal Desmos users. In fact, she and two teacher friends are organizing a free one-day conference in June to teach other math educators how to use the online tool. About 200 teachers from across Ohio have signed up to come.
“We’re hearing Desmos might be integrated into Ohio’s state testing and we want to make sure teachers know how to use it,” said Fouss, who recently found out she has been accepted as a Desmos fellow.
That kind of brand loyalty from teachers is notable given that there’s so much skepticism in the field about efforts to profit from education.
For Fouss, a 20-year veteran, the tool is a good fit because it’s platform agnostic. “We’re a bring-your-own-device school,” she said. “We have iPads, laptops, touchscreen [devices]—everything across the board. And Desmos works with everything, which is awesome.”
Many teachers note that the basics of what Desmos and a hand-held calculator can do is the same. But there are differences in layout and interactivity. For instance, on Desmos, students can zoom in and out by pinching the screen, similar to what users can do on the Google Maps app.
“With Desmos, you can just click where you need on the screen, and it shows you exactly where you want,” said Sophia Godbey, one of Fouss’ 10th grade students at Anderson High. “With a graphing calculator, you have to click a whole bunch of buttons just to get one point, and it takes a lot longer.”
There’s also a feature on Desmos called a slider that allows students to move the value of a variable up and down, causing the graph next to it to update automatically.
“The fact that students can drag their finger across the screen and change something on the screen, that’s actually a really effective tool in mathematics,” said Ensley of the Mathematical Association of America. “Especially for things like calculus, where you’re using mathematics to describe things that are changing in the real world.” Teachers can also use the many activities on the site or create their own with the activity-builder template. During an activity, they can see students’ answers all at once and display them all on the board without names attached.
“I actually really like it because we can’t judge anybody for really messing up, but you’re still able to kind of tell which one is your own,” said Godbey. “It’s really nice to be able to compare your own to everybody else’s and to the real answer.”
Distractions, though, can be a serious impediment to using online tools like Desmos, some teachers say. “The problem for me is you walk around the classroom and five kids are doing it and another 10 are watching NBA highlights on their Chromebook,” said Williams.
Texas Instruments offers thousands of free activities for teachers on its website as well. And teachers can connect classroom TI calculators if they have the Navigator system, points out Gail Burrill, an academic specialist in the mathematics education program at Michigan State University, who works as a consultant for Texas Instruments. A 15-user classroom Navigator set retails for about $2,000.
Williams, the Staten Island teacher, said his students have recently started pushing back on what they see as hand-held calculators’ outdated interfaces.
“It’s just like putting Elvis on the screen and being like, ‘Let’s rock out hip daddy-os!’ ” he said."They’re used to that iPhone touch interface.”
Desmos isn’t the only free tool with online graphing capabilities—many teachers are also using interactive online tools from GeoGebra, an Austria-based company. But as some educators note, that program is more geometry-focused and is probably more competitive with the Geometer’s Sketchpad commercial software than with hand-held graphing calculators.
However, even the most avid proponents of Desmos say they can’t completely get away from the hand-held calculators. Students still need to learn how to use them because they’re the only devices allowed, for now, on the SAT and ACT college-entrance exams.
“I can teach more material with Desmos, but if I don’t train them to use the TI, they’ll be at a disadvantage on the SAT or ACT,” said Julie Reulbach, an Algebra 2 teacher at Cannon School, a private preK-12 school in Concord, N.C., and a Desmos fellow.
So for now, many teachers say they’re using both devices. “I do specific ACT review once a week, where we’re on the graphing calculator because I want them to know the keystrokes,” said Fouss. And unless or until the testing tools change, “I have to be deliberate about making sure we’re using both platforms.”
This special report was produced with support from the Carnegie Corporation of New York. Coverage in Education Week of learning through innovative designs for school innovation is supported in part by a grant from the Carnegie Corporation of New York at www.carnegie.org. Education Week retains sole editorial control over the content of this coverage.
Coverage of learning through integrated designs for school innovation is supported in part by a grant from the Carnegie Corporation of New York at www.carnegie.org. Education Week retains sole editorial control over the content of this coverage.