Non-continuous

Hi parents. Thanks for taking a minute to read through this post.

When we started the year in Algebra I, we knew that the calculator would be taking on a bigger role than it has in the past. What we didn’t know was how difficult it was going to be to get every student on board and ready to go.

Right now we have about 25% of students that actually have the TI-Nspire technology that we are requiring. Another 20% that have a high school ready calculator (one that has graphing and pseudo-spreadsheet capabilities), and the rest of our students either have a middle school calculator or no calculator at all.

This creates two issues that are holding us back from doing and learning what we need to do and learn. The first is that students do not have a high school ready calculator. The reality is that the tools we once used to learn and do mathematics are not the best tools for the job anymore. As obvious as the difference is between a slide rule and an electronic calculator, the same differences exist between middle school and high school calculators.

The second issue we have found is that even among high school ready calculators, the technology is too different for everyone to choose their own brand and model. Cell phones come to mind for me as an analogy. Each different calculator that a student brings into the room is like a different model of cell phone – a different operating system and a different way to use each one. Imagine trying to teach a class of 30 students how to send a picture text message on 8 different types of phones all at the same time. Then, realize that a picture text message is a task which is 10 times easier than the most basic tasks we will perform on the calculators we use.

I’d like to show you a concrete example of what I mean. A large part of Algebra I is connecting algebra symbols and operations to geometric representations. If a students needs to solve an equation, we want them to know what that equation looks like from a geometry point of view and an algebra point of view at the same time. A starting point for all of this is finding the intersection of two lines. Both of the following videos accomplish the same task. The eventual goal is to turn what we do here into solving the following equation: 4.13 = -0.78x – 8.

There is a significant difference between the calculators. Teaching a room of students how to do this on just one version of the calculator can take in excess of one-half hour, not to mention trying to teach two or more versions. The overall experience is different as well which is why we are requiring the TI-Nspire. For example, in the Nspire video we stayed on one screen the entire time and watched the solution unfold. The notation is accurate and visible on the Nspire. The final solution is shown as an ordered pair (which is what we were looking for). The work on the Nspire is dynamic. Clicking on the axes allowed me to move it and resize it. If I wanted to I could have changed the lines we were using by just clicking and dragging them. By contrast, what you saw on the TI-84 (and similar calculators) was a static picture. Not movable, not explorable, just a picture.

I’ve said too much already, but I need to be clear that the technology is necessary and (since we are educating groups of students) really only works when everyone in the class is ready to go. My advice is that you check Amazon often (I just looked today and found price points of $69.99 for brand new Nspires) and also check eBay as well. Do not purchase an Nspire that has a “click-pad” and do not purchase a “CAS” version. Picutres of what you want are shown below.

Moving ahead, here is how I would like to be part of the solution. I have started doing some leg work for you and have been purchasing used-but-almost-new and brand new TI-Nspire and TI-Nspire CX (the color version) calculators from places like ebay. I will sell them to students on a first come, first serve basis for the exact amount I paid for them, including shipping. The savings over a new purchase from a store is substantial to say the least. A new TI-Nspire might go for $100 in a store but I am getting them for $46 and less so far. I will keep a list here of what I have available and update it when any are sold or replaced.

You can return the favor by letting me know when you find a good deal and I will share it here.