Customer Reviews
Does what it is supposed to do... 
2008-05-09
Casio has been making calculators since the abacus was replaced (even tho it is still being used in some places, like MIT) so it is not surprising that this device works very well and does what it is asked to do.
Great calculator, bad price 
2008-05-04
It's 5 bucks cheaper at Target, PLUS you don't have to pay for shipping, and it won't take 2+ weeks to get to you!!! It's an awesome calculator, tho I have trouble adjusting to the button placement, having always used TI calculators. Amazon took their sweet time getting it to me; by the time I got it, I didn't need it anymore. So much for getting it by the "expected arrival date" or whatever...
good description and arrived quickly 2008-04-21
This one isn't as fancy as the graphing calculators but it has a lot of the other main functionalities for geometry and trig and pre-cal, and even some calculus.
Not the most intuitive 2008-04-05
It's really a pretty cool calculator, but I do have a couple of gripes. First, the "book" that comes with it is pretty crappy, although it does contain all of the information if you take the time to dig through it. I found that your better bet is to go online and find it. At least then I can zoom it so that I can actually read it.
Second, the default setting displays all answers as improper fractions, so if you enter 5/4 you get a result of 5/4. Gee thanks, that's helpful. After several minutes of jacking with it and digging through the book, I finally found a section buried way down in the middle that shows how to switch the display to decimal (the S<>D button). I'm sure that this might have been obvious for seasoned scientific calculator users, but not for first time buyers.
Now, once you get past some of the quirks, it is a pretty good calculator. I like the textbook display. And for $18 (at Target), you can't beat it.
Always love Casio 2008-03-15
I've used Casio scientific calculators for many years. They're very durable, and especially suits a user who needs a scientific calculator without graphical functions. The display is also very explicit.
EXCELLENT PRODUCT 2008-06-30
I THINK THAT THIS CACULATOR IS GREAT FOR HIS PRICE.
I BOUGHT ONE AND MY BROTHER TOO.
I HAVE TI-30X IIS, BUT I THINK THAT THE CASIO FX-115ES IS BETTER.
Good product- good buy 2008-06-29
Easy to use, has all the functions needing for algebra, and gmat prep. Buttons are big enough for convenient usage. Good display. Over all a good buy from amazon for the price and the seller.
Best Calculator For Taking The FE 2008-06-13
The NCEES, which administers the FE and PE tests, has banned all high-end calculators, for example, the HP50 and TI89. One can only take the test with a scientific calculator from the "approved" list:
[...]
Here is a brief description of a side by side comparison of two approved machines, the HP35s and the Casio FX-115 ES. Without a doubt the Casio is the better machine:
(1) Cost: about $18 for the Casio compared to some $60 for the HP. If the only use of the calculator is for taking the test, the Casio is one-third the price of the HP. This makes the Casio the clear choice based on economics.
(2) Display: the Casio has a clear, distinct, textbook "pretty print" style of fractions and radicals. Argument entry is algebraic, and large, complicated expressions are easy to enter.
(3) Semi-symbolic logic: for example, in radian mode, "cos^-1(.5)" the Casio returns "1/3*pi", impressive for just a scientific calculator. Exact fractions and radicals are nicely done. Toggling between exact and decimal values is done at the touch of a button.
(4) No need to program: many functions on the HP, such as root-finding, have to be programmed or are hard to use. The Casio has built-in, easy to use second and third degree polynomial root-finding equations. The procedure for doing rectangular <-> polar conversions on the HP is stupid. In contrast, they are nicely done on the Casio, with a button dedicated to each one. Also included on the Casio are systems of equations, matrices, and vectors, all built-in, no programming needed.
(5) A neat feature: the Casio's integral button. Press it and an integral sign with limits pops up, easy to use. Most functions are readily integrated on the Casio, though it does choke on many root and complicated integrals.
(6) Equation solving: write an equation with X, and the Solve function on the Casio will solve it readily, every bit as good as the old HP Solver.
(6) Constants and conversions: the Casio has 40 constants and 40 conversions, which far outnumbers what the HP has.
In conclusion, the best calculator to take the test with is the Casio FX-115 ES.
Fantastic, especially for the price 2008-06-09
I'm homeschooling my 12 year old son ... he loves math and had buzzed through algebra and trig, so we started calculus this year. Much fun for both of us!
On a whim, I bought this calculator when I saw the price ($[...]) and the note that it does integrals. I thought my son would shrug his shoulders at yet another calculator. Instead, it's turned into one of his treasures. Right off, he began doing algebra on it; within an hour, he was numerically integrating functions. Lately, he's been challenging it with calculations that take ten minutes to converge. Yikes!
We've been studying physics as well, and when we were fooling with Maxwell's Equations, he'd dig the constants (permitivity & permeabilty of free space) out of the innards of the calculator.
Probably he would have loved any good calculator, but I'm delighted at how he took to this one. Simple, fairly rugged, lightweight, and cheap enough to give to a 12 year old without worries that it'll get broken or lost.
Very good quality & highly portable all around great calculator 2008-05-30
I have since changed my mind about the new Casio FX-115ES calculator. It is as good or in some ways even better than the Sharp 506WBBK unit and of course slightly higher in its price. Both units are quite small, light and yet highly useful and powerful algebraic operating system (AOS) machines, capable of performing many important mathematical operations. The Casio doesn't perform matrices of order higher than three (whereas the Sharp will perform up to 4th order matrices), but the Casio has a screen contrast control and a lot more intuitive setup and control features. The keyboard, although busy is nowhere near as busy or hard to remember as on the Sharp.
I do not use any calculator every single day anymore, but when I do, I don't want to have to reread the manual thoroughly in order to remember how to do some key mathematical operations. Simplicity should be and is the guiding principle on the Casio. Also, largely different mathematical operations are kept quite separate which I find useful, but some others may not. It too has a quite limited memory, but for what it has, it does most operations quite cleanly and quickly. It also has two large (multi-page fold-up) paper manuals (a explanatory user's guide and a separate appendix of example calculations) showing all of the numerous types of operations in more detail.
I also like very much how this calculator displays very useful information about both the conversion of physical units from one system to another as well as the values of the available physical constants (40 values are available for each of these options). On the Casio the operation being performed is explicitly stated with standard symbols given for the particular constant for example. On the Sharp 506 WBBK there are about a dozen more values available, but no information is given after the operation is performed so you may just have to look your code up again to check and/or remember the operation that you have performed.
Finally, I also like how it allows the user to keep a record on the screen of the integral or derivative that was just performed. To boot the screen adjusts its scaling for your viewing of the result depending on the level of detail of the final operation, which is quite a nice feature. It can also be adjusted to either have a standard decimal style output answer or an answer with explicit integer and fractional parts. It is this same display control that fully allows all parts of the integration process to be displayed or not as chosen by the user. In some cases, for example making a table of values of a function, it doesn't always do a good job of representing the number in the very small tabular view, but luckily it also gives a backup view of every tabular entry at the bottom of the table and in all cases these are clearly and easily read and always quite correct.
Finally, when it does comes time to change the battery there is only one to replace on the Casio, but two to change on the Sharp (all LR44's).
Now I am also awaiting the arrival of the FX-991ES PLUS (which is very close to that of the FX-115ES, but with a redesigned body shape with all plastic keys and a new snap-on cover) that was just released by Casio. The Plus version has 9 memories and can perform 417 functions which is much closer to the capabilities of the Sharp. It also has an integer random number generator capability, etc.
UPDATE: June 29, 2008:
The Sharp EL-W506 is now available from the UK and it is also a greatly improved product too (with Sharp's Write-view capability just like Casio's Natural display style VPAM). It still has a quite busy keyboard, but is so much improved over the EL-506WBBK that it deserves a careful examination compared to the Casio FX-115ES too. Probably both the Sharp EL-W506 and the Casio FX-115ES Plus (or FX-991ES Plus) will both be available for the US school market for the fall.
