TI-84 is easy to use.
Both the TI-83 and TI-84 have become the standard for use in High School math courses. I used this calculator throughout my entire high school career and never had any problems with it. It is very similar to the TI-83, but just has an increased memory capacity and a few other changes. The included USB cable is nice if you want to hook it up to your computer to download games onto the device like so many kids did. It was very easy to use, and usually a teacher would teach you how to use it. But the provided manual does help when you have questions of your own and the teacher isn't there to help you. While it isn't as advanced as a TI-89, it is perfect for the simple equations that are done in math classes all throughout high school. I would recommend this calculator to any person going into high school and are still using a cheaper version of the TI line of calculators. I guess it all depends on price if you wanted to purchase the TI-83 or this 84.