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Comment by Yossarrian22 | Hacker News Reader

Ti really needs to stop with the artificial product differentiation. There's no reason 15 years after the Nspire CX CAS came out that everyone of their calculators can't do CAS.

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CAS capabilities are prohibited in the SAT: https://satsuite.collegeboard.org/sat/what-to-bring-do/calcu...

Wow, they used to be allowed back when I was in high school. It came in super clutch for SAT but much more importantly AP. Our school mandated the original CS CAS and drilled us on how to use it effectively and I got good mileage out of it through high school testing and college.

I lost it at some point and got the version 2 and I would occasionally use it for work. I wish it had USB-C because who has a mini-B cable for charging these days

As someone who also menu-3-1'd their way through the SAT, I'm surprised it was ever allowed. Super useful outside of school but knowing that a good portion of my classmates using Ti-84s were doing the same problems on paper felt rather unfair.

Forgot what menu-3-1 is lol, I would use solve() all the time though. Got super good at typing that with my thumbs really fast

I vaguely remember they were banned by a proxy that stopped working after the Ti-89 came out: no QWERTY keyboards

Originally that blocked the Ti-92, but then the Ti-89 and Nspire line had numeric keypads + CAS

Ah yes, I had a 89 Titanium (bought with the funds from a math prize) that felt like sanctioned cheating for College Board exams. The year I took the AP physics test, there was a surreally difficult integral or differential equation that I owed completely to the calculator. I never did as well in math competitions since getting that thing, but no regrets.

CollegeBoard only seemed to realize recently, the ban on CAS calculators on the SAT, PSAT, and AP exams came last September if I remember correctly, maybe August or October

They let you write python programs as long as it’s from memory though. I wonder what the code golf looks like for a rudimentary python CAS. If you could evaluate the equation without needing to parse it, I bet you could get a lot of mileage out of a black box gradient decent routine. The analog circuit solver I wrote for my nSpire (without CAS) was ~11kB. https://github.com/deckar01/pylacc

Advanced calculators are in an unusual space with external constraints on it. Some of the features or differentiation they add serves the constraint of "if you don't, we won't let students use it in the classroom".

When a calculator is used in a classroom, there's a concern about people using the calculator to replace the skill that's being taught. So, for instance, there's space for a calculator with no CAS, for a class that's trying to teach you to do algebra. That is in some ways easier than "don't use this function of the calculator".

Yeah there's not really a purpose for advanced calculators anymore (apart from the niche market of people who just enjoy using them). Calculators are basically only a thing now to make it harder to cheat on exams. If you don't have that constraint, you might as well use Wolfram or Matlab or whatever.

Or, here's a wild idea - exam problems should be structured such that they do not require any advanced calculator.

Math problems should not require any calculator. Physics problems should require a scientific calculator. Overcomplicating the arithmetic shouldn't be the point.

That rules out classes of problem which we want to teach, or falls back to using lookup tables which is more arduous and limits the number of problems which can be put on an exam.

Teaching students to use lookup tables at all is a largely pointless exercise. Teaching students to graph or use statistical functions on an advanced calculator transfers very well to other environments.

> That rules out classes of problem which we want to teach

Does it? Could you give a contrived example of a high school problem that would be ruled out by a lack of a graphing calculator?

> Teaching students to graph

They should be able to plot any of the functions they'll be working with by hand, very quickly.

> statistical functions

If they are using statistics, they should be able to provide the relevant combinatorial coefficients as the answer (xCy, etc), without actually doing the computation.

Not to mention that scientific calculators all support basic stats functions.

You've already rejected elsewhere in the comments the style of problem these calculators are used for as either "more complicated than a high schooler is taught" or a "your teachers have wasted your time".

Which is fine, you have an idiosyncratic view of modern mathematical pedagogy (at least as it exists in the US). When you're a high school math teacher you can argue with your state dept. of ed. about it.

These calculators are also used at the undergrad level, fwiw, so the "high school level" (whatever limit you're putting on that, many high schools will accelerate students into undergrad stats and as far as Calc II), is not a factor in their use overall.

Calculators can do a lot of things; a lot of physics is greatly improved by access to a good calculator.

My linear algebra class used F_2 as our field probably half the time that it was specified. Realistically almost any course probably doesn't need calculators at all (or they could at least be kept for homework). If you're not teaching arithmetic, you keep the arithmetic simple. If you're not teaching algebra, you keep the algebra simple. etc.

It is not really classroom. It is more so setting testing standard that matches the standardised testing that schooling aims for. This ofc then extends to testing in classroom tests as that is best way to prepare students.

Not that any of this matter anymore as it can be entirely replaced with LLMs in near future.

The reason is exam requirements - some professional certifications don’t allow CAS calculators and have other restrictions.

I don't think it's been about costs or CPU for at least 20 years, but isn't it more that for kids to learn to do math, it's better not to have CAS always at hand? So that's why there are some in the lineup without it.

It doesn't help students learn if the tool does everything for them. This isn't a tool for professionals.

Heck, you could do a decent amount with the CAS back in the TI-89.

Decent? I'm not sure the new CAS models do anything that the TI-89 didn't.

Which is why it was notoriously banned from exams.

TI-89 is the GOAT!

Honest question: Why do we need physical graphing calculators anymore? Can't this just be a phone app?

That screen resolution for one is horrible for 2026.

Mostly for students in settings that may disallow either smartphones or calculators with specific advanced features (schools, SAT exams etc)

Also I don’t know about you but these days I welcome stuff that allows me to stay away from the damn phone.

i moved my ti-89 to be a phone app, but it was much much slower to type on the soft keyboard than it is to press the actual buttons.

It's about ensuring "academic honesty" on exams. Also, it's nice to have buttons rather than a touchscreen. Also, there is something to be said about using a device with a different form-factor than the one on which a student also scrolls TikTok/IG and distracts themselves otherwise.

You don't. Most academic uses are now replaced by desmos, which is also used on the SAT. It's free, it's fast, and it does most of what you need.

I am pretty sure I could use a TI-89 Titanium in the dark even now

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