I don't use my beloved TI-85 anymore because I teach with an 82 (and need to BUY an 83). Make me an offer for my TI-85, so I can buy an 83. I will sell it for the best offer..you pay shipping. It works perfectly and has lots of high school math oriented programs. email me at kasper@REMOVETHISBEFOREMAILINGcollegetrack.com