You will need a calculator for both the CEM course and the CEM test. You do not need a fancy one - $5-$10 should get you a nice, easy to read, easy to use calculator. You really only need the four basic functions -- +,-, x and / -- and the square root. We do not do anything that requires the use of trig functions or other special functions. One with scientific notation for numbers might be useful, but there are other ways to deal with the large numbers that we work with sometimes. The main thing is to have one that is big enough to see easily and to push the buttons accurately. We also do some engineering economy calculations that can be done with a $15 to $20 calculator like a TI BA-35. This calculator also does everything I mentioned above. But, we also do everything with interest tables, so you are not required to have a calculator that does the financial calculations. Your choice - a $5 basic calculator or a $20 one that also does the economic problems.