advertisement

Make your way through maze of graphing calculators

You’re on the market for a calculator, but knowing which one you or your child needs for school can be just as perplexing as any high school math formula. With plenty of options available, how do you know what you really need — and what you don’t?

Calculator usage, though sometimes seen at the elementary level, begins more in middle school or junior high, when students start studying pre-algebra and abstract concepts, teachers say. That’s when visualizing math becomes more important and where a calculator can help, they say.

But it’s in high school and college when a graphing calculator becomes “a necessity,” says Kimberley Polly, a math instructor at Harper College in Palatine, who also has taught at the middle and high school levels. “Students come out with a broader sense of functions and relations if they have been in a classroom where a graphing calculator has been used appropriately,” she says.

Before they begin shopping, a parent or student needs to know what to buy. “The first thing to do is contact the school to see if there is a required or recommended brand,” says Tysun McKay, with Texas Instruments.

Many suburban high schools and colleges, for example, require a Texas Instruments TI-83 or TI-84 calculator in the advanced math and science classes, with the latter being one of the most frequently used models, teachers say. “From an instructional viewpoint, it’s much easier if the class has all the same technology,” Polly says, so the instructor can spend time teaching the curriculum, and not technology.

In the classrooms, the calculator allows students to study investigative problems. “It’s an awesome visual tool to study relationships between variables and be able to quickly put data on a screen,” Polly says.

Before the aid of technology, for example, students were limited in what they could study by what could be put on paper. “It would take too long to plot bazillions of points to be able to see where (peaks and valleys) happen,” she says. “A calculator can plot those in an instant and students can right away see patterns.”

But do the functions justify the cost? A quick search on eBay shows the TI-84 model can run anywhere from $45 for a used one on up to $130 for a new one. And though it may be hard for some parents to swallow spending that amount on a calculator, teachers say it’s a device that’s built to last all for four years of high school and beyond. “It’s an investment,” says Ray Lesniewski, the science department chair at Jones College Prep in Chicago. He tells parents the calculator is a necessary tool in helping to increase math and science literacy that also can give students an edge on standardized tests.

Before buying, McKay says it’s important to consider what the long-term needs are. “A graphic handheld that you’re buying freshman year will take you throughout high school in both math and science courses, and could be used well into college,” she says.

For students who can’t afford the cost, teachers can loan one of the school’s sets, educators say. At Harper, for example, students can pay a small fee to borrow a model for a semester.

But technology, as we know, can change fast. Many classrooms are already moving beyond the TI-84 to the newest model available, the TI-Nspire. Robin Levine-Wissing, an instructional supervisor of math at Glenbrook North High School, says students love them. “They can explore on their own,” she says. “The students like it because they can save everything and work on it later. (Their assignment) is constantly a work in progress.”

The most recent version, the TI-Nspire CX, offers color and 3-D graphics capability and resembles a minicomputer. Jennifer McDonnell, coordinator of math and science and instructional technology for Elgin Area District U-46, says the district is switching from the TI-84 to TI-Nspire CX this year. They just bought 200 models for each high school, and leaders are offering students a deal in purchasing the model through a preferred vendor for about $25 less than the average $160 retail price. Among other things, the new calculator allows students to transfer graphics and assignments from their calculator to their laptop.

Not all teachers are convinced newest is the best. Though the TI-Nspire CX has all the bells and whistles, it also can be cumbersome, Polly says, and she prefers her students to be doing computer-like functions on the computer. “They can get in the way of learning more than they enhance it,” she says.

Regardless, teachers say they expect other suburban schools to follow in the steps of U-46 and make the TI-Nspire CX a must-have tool for students. McDonnell says district teachers already have started training.

“We’re slowly getting them all up to speed,” she says. “It’s going to change things pretty dramatically. If we’re looking at how students learn, we need to engage them. It opens up so many more doors in what can be done in the classroom.”

Graphing calculators allow students to plot many points on a graph and see the patterns immediately.
The TI-Nspire allows students to save their work for use later.

Choosing the right calculator

There are four basic types of calculators. Here’s what they are and what they do.

Basic four-function

These pocket-sized digital calculators add, subtract, multiply and divide. Some models may figure percentages and square roots. They have a one-line window display for viewing results.

What they do: Perform everyday calculations and basic math operations.

Who uses them: Anyone with simple calculating needs.

Scientific

These calculators are used to solve problems in math, science and engineering. Some have two-line displays.

What they do: Beyond basic math, they perform trig functions like sine and cosine, exponential functions and logarithmic functions, among other things.

Who uses them: Students in middle school, general and high school math and science courses.

Financial

These calculators perform basic math functions and calculator growth of money over time.

What they do: They compute rates of return on investments, calculate cash flows and compute bond prices and yields, among other things.

Who uses them: Business, finance and real estate students and professionals.

Graphing

These calculators have large displays and allow you to input data and view it as a graph.

What they do: Scientific and graphing capabilities make it easier to explore math functions, see patterns and understand concepts behind formulas.

Who uses them: Students in middle and high school and college math, as well as science and engineering professionals.

Source: Texas Instruments