If you are considering a graphic calculator for High School, you may know about Texas Instrument TI 83 or TI 84 calculators, but have you ever considered an HP 39GS?
A video is dated 2010. The current price has been changed.
Some high-end calculator users prefer HP calculators. Here are some links about the HP 39GS calculator, which seem to have more math features and functions than the TI 84.
If you have any opinions or experience, please share.