A teardown wouldn't be too interesting; it looks like the calculator is basically just one chip inside: http://www.datamath.org/BASIC/LCD_Modern/JPEG_TI-108.htm Of course, it might be interesting to look inside the chip...

Now you're thinking what I'm thinking. :) Although, I was interested in the PCB, too, since I figured it might be extra simple. That's a way to reduce cost and improve reliability vs overcomplicated components used in many modern designs. Really, really simple indeed.

Even a modern "advanced" calculator like this 2-line model[^] is just a blob chip and keypad matrix. Calculators are all extremely simple until you get to the graphing ones that have external RAM or even flash memory.

[^] http://datamath.org/Sci/Modern/JPEG_TI-30X-IIS_SWH2016.htm