The Power of the fx-991EX – It’s Not JUST Solar

I read the Casio Twitter feed and FB feed every day, just to answer questions and see what followers might be saying. Recently there have been some kudos shared about the fx-991EX solar powered scientific calculator that got me curious. In particular. that the fx-991EX does engineering problems so well and they would be lost without it (someone said he uses it in all his higher-ed courses). This was intriguing to me since I assumed engineers, with their complex calculations, would more likely use graphing calculators like the Prizm or ClassPad or even engineering software.  Naturally, I set out to explore some of the ‘engineering’ capabilities of the fx-991EX, since I hadn’t really spent too much time with this aspect of the calculator.

As I refreshed my memory of the menu and capabilities of the fx-991Ex, it kind of boggled my mind how
much this solar-powered scientific calculator can do, and with it’s QR code capabilities, it can even show graphs and printable spreadsheets and tables. (See my previous posts about Graphing & QR code capabilities). After looking a little more closely at all the menu icons and what each does, I understood why this one calculator would in fact be sufficient for engineers, or really anyone. I spent some time playing around with different features that I had not previously explored, and have shared a couple of my explorations in the video below.

For those of you who have not experienced or explored this powerful little calculator, I suggest you do. If you are at NCTM San Antonio this April, stop by the booth and get some hands-on experience, or just explore some of the videos, or download the free 90-day emulator trial and give it a go.  You can access our Quick-Start Guide to get you on your way.

Real-world Math Applications vs. “Naked” Math

During my past week off celebrating the holidays, while perusing my Facebook feed, two articles that popped up that made me very dismayed about the state of mathematical understanding. One was quite old – from the 1980’s.  Here’s the picture and information that was posted:


(Fractions.  It always comes back to fractions doesn’t it?! )While this was old, the point it was making, onw that is VERY relevant today, is that there are still misconceptions and lack of knowledge about mathematics, in particular, fractions.

The second story was from an incident just last week, where a trucker destroyed a historic bridge because she drove her semi-truck onto the bridge. The bridge had a posted 6-ton limit, and her excuse was, “I didn’t know how many pounds 6-tons was”. Forget the more obvious math discrepancy of her semi-truck having a 30-ton weight and the bridge having a stated 6-ton limit (30 IS NOT LESS than 6..?!?). Clearly there is a lot of math misunderstanding going on here!


What these two stories brought up for me is the need for teachers to really provide context to mathematical problems. When I think about how most students ‘practice’ fraction skills or conversions (the trucker situation), it is still most likely through a drill-and-kill worksheet/app situation consisting of several “naked” math problems (meaning just numbers) with no context attached. In the age of Common Core, where real-world context and application and understanding of what those fraction and conversion skills actually mean, “naked” math practice is a disservice to students. When people encounter math , outside of school, it is almost always in the context of a real-world situation – i.e. is a 1/4 pounder from McDonalds a better deal than a 1/3 pounder from A&W, or will this bridge be able to support a 30-ton truck if the limit is 6-tons. (Or, as the trucker actually asked – how many pounds is 6 tons?)  Rarely is it a “naked” math problem in the real world – i.e. compare 1/4 to 1/3 – there is ALWAYS a context that helps make sense of the problem.

It is so easy to find real-world examples of those mathematical skills we want students to know and understand, so why don’t we always make sure that students are provided a context? It helps deepen their understanding, provides parameters and a need for mathematics (i.e. “When are we ever going to use this?”), and helps students be better prepared for the reality of math around us. Sure, as a teacher, I know it is significantly easier to print out a worksheet with 20 fraction problems, or 30 times tables problems. But – wouldn’t it be better to provide 5-6 real-world context problems that accomplish the exact same things and force students to connect and apply the mathematics in a way that makes sense?

I know I am beating a dead horse here.  “Real-world” context is spewed about everywhere. But come on – a few relevant, truly applicable problems where students have to think and connect math to real situations is a lot more powerful than a page of drill-and-kill, “naked” math. Not to mention more interesting. And – if students don’t get it – the context makes it a lot easier to explain and model than a “naked” math problem.

Go on – stop being naked and get real! Math is everywhere, so go find it and use it.