The graphing calculator decision matters more than most parents realize. Pick the wrong model and your student fights the device on every homework set; pick the right one and it disappears into the background. Three calculators dominate the U.S. high-school market: the TI-84 Plus CE, the TI-Nspire CX II, and the Casio fx-9750GIII. Here's a clean comparison.

The short answer

  • If you want what your teacher uses: TI-84 Plus CE. ~80% of U.S. high schools standardize on it.
  • If you want maximum power: TI-Nspire CX II. More math features, color screen, faster CPU. Steeper learning curve.
  • If you want value: Casio fx-9750GIII. About half the price of the TI-84, fully exam-approved, but less classroom support.

TI-84 Plus CE

The current incarnation of the TI-84 family. Color backlit screen, USB rechargeable battery, slim form factor. Same operating system as the older TI-84 Plus, so any teacher's instructions work identically.

Pros: Universally supported in U.S. textbooks and prep materials. Tons of YouTube tutorials. Approved on SAT, ACT, AP, IB, and PSAT. Battery lasts a school year on one charge.

Cons: Slow CPU; complex graphs take a couple seconds to render. Older menu structure. Most expensive of the three.

Price: $130–150 new (early 2026). Used $60–90 on eBay or BookMooch.

TI-Nspire CX II

Texas Instruments' more advanced graphing calculator. Touchpad navigation, computer-style menus, ability to handle multiple representations side by side (graph + table + equation on one screen). The CAS version (Computer Algebra System) does symbolic algebra — but is banned on the ACT and on the AP Calc / AP Stats free-response section. The non-CAS version is the test-safe one.

Pros: Color screen, more powerful CPU, more sophisticated math features. Better for college-level work. Used heavily in IB programs.

Cons: Steep learning curve. Different operating system from the TI-84 — your teacher's "press 2nd → STAT" instructions won't work. Smaller community of tutorials. Less compatible with older textbooks.

Price: $150–170 new. CAS version $170–200 (avoid for U.S. testing).

Casio fx-9750GIII

Casio's flagship graphing calculator for U.S. students. Approved on SAT, ACT, AP — same exam list as the TI-84. Smaller and lighter, monochrome screen.

Pros: Less than half the cost of the TI-84. Fully exam-approved. Simpler menu structure for some operations (matrix entry, statistical lists). Built-in Python support for programming exercises.

Cons: Most U.S. teachers don't know how to walk you through Casio menus. Tutorials are mostly TI-flavored. Resale value is lower if your child outgrows it.

Price: $50–70 new — the cheapest exam-approved graphing calculator on the market.

What about the TI-84 Plus (non-CE)?

The TI-84 Plus (no "CE") is the older model — same OS, monochrome screen, AAA batteries instead of rechargeable. Still fully exam-approved. Used copies on eBay run $30–50 and work perfectly for SAT, ACT, and standard high-school math. If budget is the main constraint, this is the best value play.

What about TI-89?

The TI-89 has CAS (symbolic algebra), making it more powerful than any of the above for actually doing math. But it's banned on the ACT and on AP Calc/Stats free response. Some IB programs use it. If your student is taking AP Calc and the SAT, skip the TI-89 — they'll have to swap to a different calculator on test day anyway.

Online practice meanwhile

Whichever calculator you buy, your student will sometimes need it without it being nearby. Our TI-84 calculator handles the same scientific expressions in any browser — useful for homework verification when the device is at school or out of battery. Don't rely on it for tests (the SAT and ACT require physical calculators), but for nightly homework it covers most cases.

What about used calculators?

The TI-84 Plus and TI-84 Plus CE both hold their value remarkably well — a calculator from 5 years ago performs identically to one bought new today. eBay, Facebook Marketplace, and used-textbook sites carry plenty of inventory at $50–80, often half the new price. Verify before buying: ask for photos showing the calculator turned on, check that all keys work, confirm it's not a TI-89 (which is banned on the ACT). For Casio and Nspire, used markets are thinner — easier to buy new.

Many high schools also rent calculators for the year for $20–40. Worth asking your school's math department before purchasing if your student isn't yet sure they'll continue with calculator-required courses.

Programs and apps

The TI-84 supports user-installable programs in TI-BASIC. Common student favorites include quadratic formula solvers, distance formula apps, and simple graphing utilities. Free libraries (TICalc.org, Cemetech) host hundreds of programs — though check your school's policy first; some teachers ban student-installed programs on test days.

The TI-Nspire has a richer programming environment (TI-Nspire Basic + Lua scripting). The Casio fx-9750GIII includes Python — useful for students taking AP Computer Science alongside math.

Bottom line

If your school says "buy a TI-84," buy the TI-84 Plus CE. If they say "any approved graphing calculator," consider the Casio for half the cost. Only choose the TI-Nspire if your student already enjoys figuring out new tech — otherwise the learning curve eats the productivity gains.