The TI-83 is almost 20 years old now. When it came out, people got their dial-up internet from AOL floppy disks that came in the mail. Google was brand new, and MySpace hadn't even been thought of yet, let alone become obsolete.

But if you look at Amazon, a TI-83 or TI-84 calculator still costs $100 for a black and white screen and 6MHz Zilog CPU. It turns out that TI has done a great job with their marketing. They worked with Pearson textbooks to make sure that they are integrated into the technology solutions of high school math problems. Not only that, they have worked with standardized tests like the SAT and ACT to make sure they are the only approved calculator.

http://www.mic.com/articles/125829/your-old-texas-instruments-graphing-calculator-still-costs-a-fortune-heres-why

It's a profitable technological incumbency that is nearly monopolistic. In the 2013-2014 school year, Texas Instruments sold 93% of all graphing calculators in the U.S. The Washington Post estimates that TI is manufacturing the calculators for $15 to $20 and achieving a more than 50% profit margin, making calculators one of the company's most profitable items.

There's no reason they should cost so much, and it's shutting out students who can't afford them. Just this past week, Amazon started selling Internet-capable Kindle tablets for $50 each. But a new TI-84 still runs a retail price of $100, and classrooms that use TI-Nspires (the newest addition to the TI line) are shelling out $140 a pop — about the price of a brand new Chromebook. All for a calculator that is older than the .MP3 file extension.

I wonder how much longer this can last given the proliferation of smart phones in the classroom. An iPhone has orders of magnitude more processing power than one of those TI calculators, and everybody already has them.