Graphing Calculators Replace PCs For Mathematics Instruction

Looking at the Texas Instruments TI-92 mathematics instructional tool, itís easy to see why both students and teachers like it so much. For students who grew up handling video game controllers , the unit fits comfortably in both hands, with a horizontal orientation that suits its 240 x 128-pixel display. It even has an eight-direction thumbpad like many video game controllers, complementing its full QWERTY keyboard, separate function keys and numeric keypad.

For teachers, the TI-92ís functionality and versatility are just some of the reasons for its popularity. It handles a broad range of math from algebra through calculus including interactive geometry, symbolic manipulation, statistics and even 3D graphing.

Best of all, the TI-92 has been priced with the notion of giving each student their own, powerful mathematics tool. Sounds great, right? But d'es it all come together in the classroom? Can this hand-held unit replace, or even supplement, traditional PC-based mathematics instruction? In answer to these very important questions, Kathy Longhart, mathematics teacher at Flathead High School in Kalispell, Montana, would give a resounding ìYes!î

PCs vs. Calculators

In 1992, while teaching a new curriculum that had been specifically written to take advantage of technology, Longhart and the teachers at Flathead High School tried using traditional computers in a lab-based setting to teach mathematics. However, this initial effort did not prove to be a very successful experiment.

With four kids to a computer, each student had to share time and space, making sure the technologically adept or mathematically inclined didnít ìhogî the machine. The more reticent students would sit back and, while not participating, let those so inclined make good use of the lab time. And when class was over, the computers, with their math software, stayed put, while the students who needed them went home.

Enter the TI-92. Now, Flathead High School has three classroom sets of these mathematics tools, which works out to about 80 or 90 calculators. Longhart uses them in all three of the mathematics classes she teaches, starting with her Math 2 class.

ìThe TI-92 has a symbolic manipulator, data package, geometry package and graphing package in one unit, and I like to pick problems where we do a lot of moving between the packages,î she says. ìBy incorporating all of the packages, we can look at more powerful problems.î The calculator even has a two-graph mode for creating separate graphing environments, letting one compare different functions and graphs.

Longhart mentions that the unit acts as a kind of ìelectronic chalkboard, where students can manipulate problems by hand.î They type problems into the calculator using its standard-style keyboard and keypad, and the calculator lets them do the same manipulations that they would do on paper, with one important difference: it lets them instantly see if they are correct.

Instead of shuffling through a time-consuming calculation, marking up an entire page and finally realizing that a minor arithmetic mistake screwed up what was otherwise a correct procedure, the calculator simply d'esnít make these kinds of errors, letting students concentrate on learning procedures and formulas rather than worrying about every arithmetic problem that needs to be solved.

Students Vote with Own Money

After getting used to the TI-92s, students actually ask Longhart to go get them, she says. "At first, my Math 2 class was a bit frustrated because I hadnít given them enough guidance," she admits. But after showing them how helpful the calculators could be, her students had a change of heart. About 40 or 50 students have even purchased their own TI-92, which speaks spades about the students' opinions of the calculator.

For those who donít have their own, the school lets them check out calculators to take home for homework. "I love [the TI-92], I think it's great. It's easy to learn, very user-friendly," mentions Longhart. "You don't get bogged down teaching a machine, you can focus on teaching math."

This article originally appeared in the 04/01/1997 issue of THE Journal.