Summary: I purchased mine for $49. Its suitable for any classes through college algebra. For trig you'll want to upgrade as it doesn't graph polar coordinates though it does convert rectangular to polar and back. If you needed to you could program it to input the (x,y) into a parametric graph and so display the results. While my class mates were worrying about how to get their TI's to work I was working on the problems.
Summary: This calculator has many good features. Large enough for keys to be easily used, but fits in a shirt pocket. Uses two cheap AAA bstteries with a button battery for memory backup. It has a detailed instruction book, But the MEMORY is next to IMPOSSIBLE to access. The calculator does not even use the word memory, but uses the word list.
Summary: Other than students few need, or can use graphing calculators. Although this calculator is advertised as being useful up to and including the calculus it is best used in Pre-Algebra and Algebra I. This is a very inexpensive graphing calculator and is, thus, very slow, the screen is pretty hard to read and the instruction book not only hard to follow and very demanding but printed on paper so thin that one can read the second page through the first.