Classroom Calculator
Four free calculators on one page: Basic, Fraction, Scientific and Graphing. Change the colors, make the keys bigger, or have every answer read aloud, so every student can use it.
- Free
- No ads
- 4 calculators
- High contrast
- Reads answers aloud
- No sign-up
One calculator page for every student
Pick the calculator the lesson needs: Basic for grades K–3, Fraction for grades 3–6, a Scientific calculator that works like the TI-30XIIS for grades 6–12, and Graphing for grades 8–12. Every one of them has the same accessibility settings: high contrast color looks or your own colors for the answer screen and keys, bigger keys and answers, a font made for low vision, and spoken keys and answers. On a wide screen, the projector panel shows a large copy of the screen and every key you press.
How the Classroom Calculator works
Pick the calculator the lesson needs
Basic, Fraction, Scientific and Graphing sit at the top of the page, each with its grades. Each one has its own link, like flintk12.com/calculator#fraction, so you can send students straight to the right one.
Pick a look that's easy to see
Open Accessibility and choose a high contrast look, like Yellow on Black or Blue on Yellow, or Clear view for flat keys with no shine. The calculator changes as soon as you pick one.
Make the keys and answers bigger
On the Size tab, pick large keys or keys that fill the screen, make the answer up to three times bigger, and switch to Atkinson Hyperlegible, a font made for readers with low vision.
Hear each key and every answer
On the Sound tab, turn on Say each key and Say the answer, and set how fast the voice talks. Touch to hear says a key's name on the first tap and presses it on the second, and the speaker button beside the screen says the last answer again.
What's in the Classroom Calculator
Basic and Fraction for younger students
Basic, for grades K–3, has big number keys, memory and square root. Fraction, for grades 3–6, shows fractions stacked the way they're written, enters mixed numbers with Unit, simplifies answers and switches between fractions and decimals with F◂▸D. ÷R divides with a remainder.
A Scientific calculator with a projector panel
Scientific works like the TI-30XIIS, with 2nd functions, menus, fractions, statistics and memory. On a wide screen, like a smart board, the projector panel shows a large copy of the screen and lists every key you press, one calculation per line, so students can copy the sequence onto their own calculators.
Graphing students can see, trace and hear
Type up to four equations and the graph draws as you type. Trace a curve with the arrow keys, jump to zeros, high and low points and crossings with N, open a table of values, and press Play graph to hear the curve as a tone that rises and falls.
Your own colors, checked for you
Customize colors sets the answer screen and each kind of key to any colors you like. Every pair gets a contrast check: Easy to read, Okay or Hard to read. Fix it changes a hard pair to one that's easy to read.
One link for each student's setup
Set the calculator up for a student, then open Share to make a link and a QR code. Open the link or scan the code on the student's device, and their calculator, colors, sizes and sound settings are on. The settings travel inside the link.
Use the keyboard, or listen instead
The keyboard presses the same calculator keys, so the projector panel still shows students what to press. Turn on spoken answers and every answer is read the way a teacher would say it, like 3 and 1 half.
- 0–9+-*/
- Numbers and operations
- Enter
- =
- Esc
- Clear
- ShiftR
- Say the last answer again
- ←→
- Trace a graph
- N
- Next zero, high or low point
- P
- Play the graph as sound
Teacher controls
Full screen hides the browser around the calculator. Settings turns the projector panel on or off, resets one calculator's memory and past entries, or erases everything, including the accessibility settings this browser saved.
Built for every student
- High contrast looks, like yellow on black, or your own colors for the answer screen and each kind of key, with a check that tells you when a pair is hard to read.
- Bigger keys and answers, and Atkinson Hyperlegible, a font made for readers with low vision.
- Spoken keys and answers, and a touch-to-hear mode: the first tap says the key, the second tap presses it.
- Works with screen readers, keyboards and browser zoom, and never shows ads or pop-ups.
- Make a link or QR code with a student's settings, so their setup opens on any device.
No accounts, and nothing leaves the computer
The Classroom Calculator needs no accounts and sends nothing to Flint. Settings, memory and past entries are saved only in the browser on that computer, and a student link carries settings in the link itself. Erase everything in Settings removes them.
Classroom Calculator questions
What is the Classroom Calculator?
A free page with four calculators that run in a web browser: Basic, Fraction, Scientific (it works like the TI-30XIIS) and Graphing. On a wide screen, a projector panel shows a large copy of the screen and the keys you pressed.
Is it made by Texas Instruments?
No. Flint built it so teachers can show TI-30XIIS key sequences on the board. TI-30XIIS is a trademark of Texas Instruments, and Flint is not affiliated with Texas Instruments.
How is it different from a real TI-30XIIS?
The top line shows a few more characters, so long entries scroll less. RAND uses its own random sequence, so seeded values differ. There is no automatic power-off. It doesn't give a SYNTAX error for very long entries the way the real calculator does. Keyboard and tips lists every difference.
What grades is it for?
All of them. Basic is made for grades K–3, Fraction for grades 3–6, Scientific for grades 6–12 and Graphing for grades 8–12.
Can a student with low vision use it?
Yes. Open Accessibility in the top bar to pick a high contrast look or set your own colors for the answer screen and keys, make the keys and answers bigger, switch to a font made for low vision, and turn on spoken keys and answers. It also works with screen readers and browser zoom.
How do I give a student their settings on another device?
Set it up for the student, then open Accessibility, choose Share and make a link. Open the link or scan its QR code on the student's device and their colors, sizes and sound settings are on.
Can a blind student use the graphing calculator?
Yes. Every equation has a table of values a screen reader can read. On the graph, the arrow keys trace the curve and say each point, N jumps to zeros, high and low points and crossings, and P plays the curve as a tone that rises and falls.
How do I show the keys I press?
Turn on the projector panel with the screen button in the top bar. It needs a wide screen, like a smartboard, and turns on by itself on one. Each calculation gets its own line of keys.
Can I use my keyboard?
Yes. Number keys, operations, Enter, Esc and arrow keys work, and letters stand in for other keys, such as s for SIN and f for A b/c. Keyboard and tips in the top bar lists them all.
Does it do fractions and statistics?
Yes. The Fraction calculator shows fractions stacked and enters mixed numbers with Unit. On Scientific, A b/c enters fractions and mixed numbers, and 2nd F◂▸D switches between a fraction and a decimal. 2nd STAT picks one-variable or two-variable statistics, DATA enters the data and STATVAR shows the results.
How do 2nd and the menus work on Scientific?
Each key has a second function printed in blue above it, like √ above x². Press 2nd, then the key. PRB, DRG, STO▸, DATA and STATVAR open a menu on the top line: move with ◀ and ▶, then press = to choose. ▲ and ▼ bring back earlier entries to edit and work out again.
Do students need accounts?
No. There are no accounts or sign-ins for you or your students.
What do I need to run it?
A web browser on a smartboard, projector or laptop. Students can also open it on their own devices.
Tell us what your class thinks
Send an idea or a bug. Every message goes to the Flint team that built the Classroom Calculator.
