I got this as a junior in high school.  I'm now a junior at one of the service academies.  I think I've had to replace the batteries once in that 4 year time frame.  I am an operations research major (read applied math...), and this calculator has absolutely everything needed for any technical major.  Being able to integrate is real helpful when you want to prove something works to yourself, or just check your work.  The 3-d graphing is also amazing.  I used to have all the games on it, and they work fine.  Don't get this to pass time in class... a palm pilot has better apps.  If you have any aspirations of being an engineer or math major, this calc will help tremendously.  Definately worthy of your hard earned $$.