The *NEW* Calculator for the GED - TI-30XS

How many of you have heard that the 2014 GED assessment will no longer use the Casio Calculator?  Do you know how to use this new Texas Instruments, TI-30XS? Do you have lessons that you can teach in your classroom?

Good News!  There are 15 lessons on the TI Website, click here: http://education.ti.com/en/us/activities/explorations-series-books/activitybook_30xiis_activities

I have been reviewing these for my classroom and thought perhaps the group might want to have this information, too.  If you use one of these lessons, would you please post which one, if you modified it, and the learners reactions?  I will do the same since we are starting classes next week for FY14!

If you know of other resources, please post and share, too. 

Best,

Brooke Istas
Subject Matter Expert
Math and Numeracy Group

 

Comments

I have seen the new TI calculator for the GED. I have a major concern about a key that is not on the keyboard.

Where is the equal sign?  There is no = key.

That means: Students who think of = as an ACTION instead of a relationship are having that incorrect understanding reinforced by the new calculator.

Yes, both sides of the equation (7 + 13   and 20, for example) are shown on the screen. That only reinforces a student's sense that = means "turns into."

That understanding of = is one of the roadblocks from thinking about numbers as arithmetic to thinking about equations and relationships in algebra.

How many math books have a thorough lesson on the meaning of = as a relationship? How many of our students already think of = as an action?

Dorothea Steinke

 

 

Hi Dorothea,

I have a Texas Instrument 30X calculator sitting next to me and it does indeed have an equal sign - bottom right corner - shares the key with "enter".  This is the one my son is required to use in middle/high school math.  His is the IIS model - and the website that Brooke posts for activities is on this model.  Not sure but perhaps the one you are looking at is not the right model?

Hope this helps.

Marie Cora

 

 

Dorothea and Marie,

Here is a picture of the new calculator and Dorothea is correct there isn't an "=" sign on the faceplate.  However, there is the word ENTER.  The majority of learners already think that the equal sign ("=") means "to do something" or "the next step is".  By removing the symbol, it should allow us, practitioners, to talk and teach about equivalence and help learners to understand that when they see the "=" it doesn't mean "do something" it means "I am the same as".  Whereas, the word ENTER means "to do something".

This is what I have seen in my classroom regarding the equal sign:

x = y - 5 = x + 5 = y

This is VERY confusing and incorrect because equality is transitive, a = b and b = c, then a = c, but in the above example x does not equat x + 5.  It would be better to use a different type of symbol, perhaps an "if and only if"  which looks something like <------> (this is best I could do since Math Symbols aren't currently available on this text page).  Therefore the problem could be re-written:

x = y - 5 <---> x + 5 = y

Now, the problem isn't confusing.  As we move to more algebraic reasoning, understanding the proper meaning of "=" will be important. This is why I believe the equal sign has been removed from this calculator.

Anyone else in the community have ideas about why the equal sign has been removed?

Brooke

 

 

I am looking at my TI83 that I've had for almost a decade now and it has only an "enter" button.  It has text by the button, and that text says "solve"...  again indicating an action as opposed to a math definition.

When I think about design choices they may not consider everything that you all do as experienced educators.  They are computer guys telling the mini computer to do something. I spent many years teaching low level math in which we used very simple calculators 20 buttons at most, one of which was an equal sign.  I would use my trusty TI83 in tandem during class and while it does have an "=" sign for graphing and programming purposes, I honestly never noticed the lack of an = sign for every day equations.

Thanks dorothea for pointing that out, it is an important distinction.

More than why the designers chose the lack of an "=" I wonder why GED did they have their pick after all.  I am learning a lot from this discussion so forgive my ignorance, How long has the GED had a specific caluculator as opposed to simply having individuals or institutions provide them based on a set of "calculator requirements" like other standardized tests?"

 

I agree with what has been said. I find this calculator to be very complex compared to the old one students had worked with. I hope to try these lessons to become more acquainted and comfortable. I really don't agree with the notion of no equal sign. It is a very important symbol in mathematics!

Doing fractions only gives improper fraction results unless you know the right keys to push. I will be studying it a lot to be able to teach it to my students.

Thanks for sharing these lessons. I'm planning to try them out on myself to get over my fear of this new device.

I have been collecting calculators since the early 1980's and most of them do not have a button labelled "=" which you press to have it carry out some operation.  My collection of 'scientific' calculators includes the HP 15C, TI 81, 82, 83, 85, 86, and Casio fx-7000GA and all of these have a button labelled "Enter" [except the Casio has an EXE-cute button], and most also have a second (alternate) function for this button like Entry or Solve.  The only 'scientific' calculators I have which contain a "=" button are the TI 30 Xa (~1997) and Sharp EL-506 H. 

On the other hand, most of the widely used simple 4-function calculators, and the earlier 'educational' calculators like the TI 34 and Math Explorer all have the "=" button to initiate action.  I think this was a bad choice of label, and I'm hoping that more new 'educational' calculators like the TI 30XS will instead use the label "Enter".   (My TI 30X IIS has both Enter and = on the activate button.)

About the = sign, and calculation.

The = sign is not used in mathematics to signify an action or a command to do something, but rather a CLAIM about the result(s) of calculation(s).  The claim is made by the writer, and the reader may believe it, or doubt it and try to verify it for themself.  

The = sign is shorthand (a nickname) for "has the same value or weight as" , and NOT for "is the same as".

(1.)  Its initial use in elementary school is more restrictive: given an expression Expr (such as 7+5) and an explicit number C (such as 12), we write

Expr = C     or alternatively   C = Expr      simply as shorthand for:

IF you evaluate expression Expr THEN the result will be the explicit number C.

[Think of a baking class where the baker comes in with a recipe Expr and a cake C, and says to the class:  IF you follow this recipe exactly the result will be a cake just like this C.]

Calculators are tools built to make numerical calculations easy for humans, but of course they have their limits -- the answers they give are mainly approximations to some ideal exact result.  If the numbers aren't too small or too large, and involve only integers or rational numbers, some calculators may be able to do exact arithmetic.  There is also the possibility that it will give you an approximate numerical answer in a form you don't want: 19 decimal digits, scientific notation, improper fractions, rounded to 5 decimal places, ... and you may want to transform that into a more agreeable form.

Calculators used in educational settings mostly have delayed evaluation and some level of parsing expression shorthand, unlike simple 4-function calculators.  For example, the sequence of button presses 3, +, 4, X  will show 7 on the screen, and then followed by pressing 5, = will yield the final result 35 on a simple calculator.  On a TI Math Explorer the button presses 3, +, 4, X will continue to show 4 on the screen, and when followed by pressing 5, = will yield the final result 23.  Here we might write our input as 3 + 4 X 5  and it first parses that as (3 + (4 X 5)) and then proceeds to evaluate this expression in 2 steps as (3 + 20) and then 23.  If I use my TI-83 and type in 3+4*5 it will appear that way on the screen (and I could edit it, a great advantage) and when I press Enter it first parses my shorthand formula and then evaluates it to yield 23.  Even if I type in 3+4+5 my TI83 has to first parse this into a standard form ((3+4)+5) before evaluating it in 2 steps as (7+5) and then 12.  A calculator can only add 2 numbers at a time, not 3 or more.

(2.)  But there is a more important use for = than that listed above in (1.) .  Namely, if we have two expressions Expr1 and Expr2, we are often interested in knowing whether the VALUES of Expr1 and of Expr2 are in fact the same number.  The claim that this is so is written in shortened form as Expr1 = Expr2.  This is the form in which most of the fundamental properties of numbers and operations in elementary mathematics are stated -- of course with quantifiers to make them as general as possible. 

For example:

Associative Prop. of +: For all expressions A, B, C it is the case that (A+B)+C = A+(B+C)

Distributive Prop. of * over + : For all expressions A,B,C it is the case that (A+B)*C = (A*C) + (B*C)

One of the usual rules of algebra:  For all expressions A,B,C, IF A = B  THEN also (A+C) = (B+C).

[The baker brings to class two somewhat different recipes Rec1 and Rec2, but no cake.  Then the baker claims that: IF you follow each of these recipes exactly, the results will be essentially the same (indistinguishable). i.e. Rec1 = Rec2

Am I understanding correctly that in the actual test you do not use the TI30xs?  

It seems that they will use an onscreen virtual representation of the calculator.  For those that are interested you can go to the calculator page http://www.gedtestingservice.com/educators/ticalc. It has a video tutorial which speaks of 2002 quite often, I guess that means this has been in the works for a while. The page itself is up to date.

For those of you in the classroom, would an onscreen calculator affect your lessons and approach to preparing the students?

 

 

I'm not a math teacher, but I teach a GED Technology Preparation course. It's my job to know all of the technological skills that students will need (including how to navigate through the calculator) and to teach those skills to the students so that nothing is new when it comes time to take the test.

They'll know where to click for the calculator, for the symbols button, how to flag a test question, how to physically drag & drop those bars into the bar graph, how to use the hotspot, etc.

We did purchase the emulator software from Texas Instruments, and I make it a part of my heterogeneous class each day to give them a "math warmup" just to get them used to using the calculator. I have them practice using the numeric keypad, and also using the mouse to press the buttons on the on-screen calculator. I'm thankful for the information I've seen on this site that allows me to give more sample math problems, but I'm looking for some more - very basic ones. Like I said, I have a very very heterogeneous group (is that a real phrase?) and some are very low in math skills but I just want everyone to be able to get some practice with the buttons themselves. So the math problems can't be too advanced (which it looks liek most are on the http://education.ti.com/en/us/activities/explorations-series-books/activitybook_30xiis_activities web site)

If anyone has sample lesson plans that focus simply on getting a good grasp of the calculator keys - or just a list of math problems that utilize most of the keys on the TI 30xs, I'd love it if you shared them please.

With regards to the "no equals" sign, something I do focus on is giving them the math problem, and then discussing "okay, if your computer was not working great and you only had access to the numeric keypad, how would you do five times six?" and we then discuss which buttons to press, which includes pressing enter instead of equals.

I've tried to start a conversation surrounding the issues/ new skills/ new content of the GED 2014 test in a group on Edmodo if anyone would like to join.

(Or maybe this is the place on lincs and I've found what I've been looking for in a PLN for GED 2014 teachers!!!)

https://edmo.do/j/xu5bna

 

Thanks!

Amy

 

Brooke,

Thank you so much for sharing the link to these lessons.  I have printed them and intend to start using them this week.  We should be receiving our new calculators on Thursday (they were backordered).  I think these will be very useful to the students I am currently working with.  We are studying many of these concepts right now and this will be a great addition to the lesson, while preparing them for the new test.

GREAT!  Let us know if you learners liked them, if you made changes, or if you created your own!  This is great information for all of us who are struggling to learn and teach this new calculator.

Brooke