The only TI-30Xa calculator now being sold by Texas Instruments in the USA is the battery version:
On this page you will find links to very helpful YouTube videos that explain how to use the Texas Instruments TI-30Xa calculator (battery-powered). This is the only calculator that I can personally recommend to the students in my chemistry courses at NYIT. It is inexpensive, easy to learn, and it has many features that you will be able to use in your chemistry courses. The only version presently available in the USA is the battery-powered TI-30Xa calculator. It is possible to replace a bad battery on such a calculator, but only if you use a miniature Phillips screwdriver to remove the back cover and gain access to the battery holder (a real nuisance in my personal opinon).
A solar version was made by TI for years, but has now been discontinued in the USA. In other countries, TI still sells the solar-powered TI-30 eco RS calculator. (If you click on the preceding hyperlink, you will be directed to a web site in the United Kingdom in which TI describes both calculators. Unfortunately, Texas Instruments does not sell any TI-30 eco RS solar calculators in the USA.) For this reason, the best way for you to purchase any TI-30X solar calculator is to search for one on ebay. (Click here to perform the search.) The results of the search (if performed) will appear in a separate window. Be sure to check out the rating of the ebay seller before bidding to determine how reliable they are, because I cannot be responsible for any problems that you may experience as a result of using ebay.
On exams, I do not allow any students to use graphical calculators with alphanumeric memory (such as the TI calculators that are required by our Mathematics Department) because those graphical calculators may be used by students to cheat on exams. (You have the ability to store alphanumeric information in the calculator's memory prior to taking the exam. If you do this, you will then be able to recall that information during the exam without the professor's knowledge.)
Please note that I do not recommend that you use a TI 30-X IIS calculator, because that calculator does not have the EE (Enter Exponent) key in the usual place. Instead, the EE function in the TI-30X IIS is the second function of the reciprocal [1/x] key. In my opinion, it is a real nuisance to enter numbers in scientific notation into this TI-30X IIS calculator, because you will need to press 2nd and then EE each time you want to use to enter a number written in scientific notation into that calculator. Save yourself the torture of doing this throughout your chemistry courses; just buy the TI-30Xa and you will completely avoid this problem.
Simply scroll down and play whatever videos you are interested in looking at. Remember that you can maximixe the video (switch to full screen) by clicking on the full screen icon in the lower right hand corner. Then use the escape key to return to normal mode.
For complete information on all Texas Instruments calculators that have ever been manufactured, the following web site created by Joerg Woerner is very interesting and informative: www.datamath.org