We also buy them from the local pawn shop. $35 for the last one we bought...they had a few different models.
Do you have a smart phone or an itouch? Look for an app!
Not a good idea!! Most math professors forbid the use of communications devices (any type of cell phone) while in the classroom.
If you need a graphing cacluator, the big-box discounters or office supply stores should be your first stop -- otherwise, I would check the eBay market to see what they go for after a semester's worth of use.
Well what about the itouch?
Well what about the itouch?