I use my TI-89 Daily as well. It really is an awesome calculator. I still have my TI-92 which is Huge. It basically has the same software as the 89. It is amazing all the things that these calculators can do.
I only get the 92 out a few times a year to check the batteries are not going bad/corroding and to play games on it for a few minutes to remind me of my school days. I do have Tetris on it 
I wish I could find my HP-67 and HP-41CX calculators now. Those bring serious money on Ebay. Alas, all I have left are about a dozen lesser models.
If you can find lithium batteries of the size you need, they are much much less likely to leak than alkaline batteries. I use them wherever a leak would be expensive and sad. They are worth the additional cost.
So much love for the TI calculators here.
Let me be the first to say that I hate them, and here is why:
Not a chance, Iâm framing my first dead tube and putting it on the wall. Of course, the frame will be made on the Glowforge after the new tube is installed. 
Ah man, I had the same idea! 
I have one of those. Back in the day its ability to do integrals and derivatives and stuff was impressive, as was its geometry app. It was a lot of fun to show off. I never used it half as much as the HP 48G, though. Mostly because Iâd been using the 48 daily for a year or two by then. And probably also because it didnât fit in my pocket, so I didnât have it on me all the time. (I used the 48G as my watch and alarm clock.)
So whatâs the problem? The first article seems to be pushing that technology has surpassed the calculator industry, and that smart phones are far more capable than these calculators. This is true. They then state that TI should lower their prices to reflect this. The second article is geared towards statistics students, so not relevant for everyone, but pushes something called âRâ. I assume that is a piece of software that does statistics calculations. The author, by the looks of his other articles, programs for R, and is therefore biased to push for itâs use. He also mentions Casio as a cheaper, but better option to TI. Neither article seems to mention HP, which when I was in school, was the ONLY other viable option to the TI.
So one pushes for the use of app-enabled smart phones and the other for a piece of software.
Hereâs the problem with that. Smart phones and computers arenât allowed in tests. To take the SAT you need a calculator, and a graphing calculator is recommended. Therefore every student should acquire a graphing calculator.
Doing some quick Amazon comparison shopping, one graphing calculator seems pretty much equivalent to the next. All are very similar in both stats and cost, with Casio being the most expensive at $150. The HP is $114, and the TI Nspire is $130. This is for the color graphing calculator for each company.
Knowing that we are required to get a graphing calculator to be able to take tests, and that all graphing calculators are created equally (approximately), the issue then comes down to business practices. TI donates to schools to get their product recommended. My guess is that Casio and HP are also both heavily invested in salespeople to do exactly the same thing. Maybe TI has better school pricing, and are therefore more successful, and are therefore more able to donate? I donât know, but I wouldnât assume that they are the only ones pushing that particular agenda. And it isnât like this is a big company pushing out the mom & pop companies. TI, HP and Casio are all HUGE companies. Also, pushing forward to the college level, I donât know about you, but all of my computer labs were branded and all of the computers inside were of that brand. I had to learn CAD in the âBentley Labâ on Bentley Microstation when AutoCAD is used by 95% of the consulting world.
As for schools requiring a specific calculator⌠if I recall correctly, the TI was recommended when I was in high school. I canât say that it was required, because Iâm pretty sure one of the students in my class had an HP - he was on his own as to the functionality because the class was taught based on the TI interface, but he made due. On top of that, it was a higher-level class, so it isnât like they require every student in the school to buy an expensive calculator. As for the kids that canât afford it⌠there are options now that didnât exist when I was in school. Just today a TI-89 sold on eBay for $28 in working condition.
Is there something that I am not considering that garners âhateâ for TI?
In the mid nineties our school owned some TIs that they rented to kids that couldnât afford/didnât want to purchase. Class taught on TI interface. Pretty standard still
Since smartphones are so powerful, is there an app that lets you use your phone like a color graphing calculator? Spend $20 for the app instead of $100+ for a calculator. - Rich
Youâll need to keep the cardboard and foam box that it ships in - itâs very specialized (and expensive). Itâs expensive, premium packaging to make it easy to unbox/re-box and make sure your Glowforge can survive the mail safely.
Not hate for Texas Instruments overall. Just the TI-series of calculators and how they are forced onto students.
I hate that I was forced to buy two different (specific) TI calculators for ridiculous prices, once in high-school and again in college. The textbooks and teaching plans in use required them. Not being a maths person, I found that what I was being taught was how to press a specific series of buttons, with very little or no explanation of what was the calculator was doing. I never used either calculator again. Granted this is specific to me: I have never had a math teacher that I liked. A math teacher was the only teacher to ever strike me.
R is a GNU project, is free, and runs on most platforms. It is also used by many companies, and knowing it would give any high-schooler a head start for a decent job. Tell your job interviewer that you know how to use a TI-89, and they will probably just shrug.
None of our computer labs were branded, in either high school or university, although one of the ones in high school was donated by Autodesk (I think). When I tried to look it up, all I saw was a grant from RJ Reynolds Nabisco⌠and I never once heard about that when I was student. There was certainly no Nabisco Lab.
I would say that you have a valid reason to dislike.
I never bought my TI; I rented it. I didnât understand the principles, and that made it really hard for me to know whether I had put the equation in correctly. Late algebra and all of trig evaded me.
I donât think Iâm too stupid for math; but the problem is that math is taught by people that get it instinctively, and they donât relate to me. Or you. Add a layer of abstraction by programming a calculator, and I was lost. Managed to get through a Bachelorâs degree without a single math class.
Is that a requirement for warranty service?
You will want to keep the box, warranty item or not.
Itâs an odd size - the closest thing i can find on U-Line is the double wall 275 pound test box and itâs slightly too small - $13.75 per box, but you have to buy a minimum bundle of five. You would probably need to go up to a special order.
So itâs going to cost you at least $70 plus shipping (no idea how much that is for something that size - 47lb.) to try to replace the box.
You can cut the tape on the box and store it flat, then re-tape it when you need it for shipping, but it would be idiotic to not keep the box. And the special foam inserts that center the unit. Find a place for them in the attic, or do what Iâve done and leave it standing next to the dining table. (Itâs a nice conversation piece - all the neighbors have asked, and then of course, they have to see the laser.) 
I thought I saw @dan say the box canât be broken down without sacrificing its integrity. Might go back to the warranty repair question. If I can break it down, no problem. Otherwise, Iâve only got 1440 sq ft of house, 1 wife, 3 kids, 2 cats, and 2 guinea pigs. Iâve no room for large empty boxes that serve no frequent purpose.
Iâve got tape thatâs better than what comes on the box, unless they are planning to change what they use now. (And they might be planning toâŚI donât know.) But donât break down the foam - it is a stiff structured foam, and that would destroy the integrity.
So i guess youâd still have to find a place to store thatâŚmight as well keep it in the box.
HmmmmnâŚattic?
Assuming thereâs not some reason excessive heat would be an issue for it, thatâs exactly what I plan to do.
Attic = Daughterâs bedroom. Iâll have to see what my options are when I get it. Mostly I want to know if itâs a requirement for warranty repair/replacement. That kind of makes the decision for me.
If you werenât into math, what class did you take in high school that required a graphing calculator? In my high school there was just one, linear algebra and you had to get permission to take it. I guess if you took a statistics class, they usually required the TI-83, though I recall that at the college level, not the high school level.
For me it was cool to have to get the expensive gadget. And again in junior college when I upgraded to the 89 so I could do symbolic differential equations (no other one on the market at the time would do them). My parents paid for them both times, so that aspect of it didnât phase me I guess.
Still, if you arenât a math person you arenât going to care about a calculator, and you arenât going to use higher functionality on them, except for test taking. As an engineer I used that calculator for all of junior college, all of college, every major test (except one which I had to get a scientific calculator for - couldnât use a calculator that had âmemoryâ), and a majority of the time in the professional world. Granted, I donât use itâs higher functionality much these days, but its there if I need it.
If I told my interviewer that I knew âRâ they would congratulate me on watching Sesame Street. I donât think Iâve ever had a job where they would even know what it is. I had certainly never heard of it until today.
Did you go to a private college? I think state schools need more help in the outfitting of their labs⌠particularly technical state schools (Cal Poly Pomona).
I also get the feeling that we are different generations. I graduated high school in '95.
