Texas Instruments TI-83 Plus graphing calculator. It works. The photo shows it powered on and running calculations, so you can see the screen is good and the keypad responds. Plastic has the usual scuffs and scratches from use, nothing that affects how it runs.
Two things to know before you come get it. Batteries are not included, so bring your own. The slide cover shown is a Texas Instruments cover off a different model. It fits over the keypad and protects it fine, but it is not the factory cover for this machine.
Still approved for the SAT, ACT, PSAT and AP exams, so it covers algebra through calculus and statistics.