1
Open the dock and tap Calculator
It lands on your board with a clear display and big keys.
The dock · Subject tools
Calculator
A big, board-sized calculator for working it out together.
The four operations at a size the whole class can follow. Model the working on the board instead of narrating at a tiny desk calculator.
- Free for teachers · no login required
0
How it works
Three steps, zero setup
No setup screen, no import wizard — Calculator lives on the same board as everything else and it's running before the class has sat down.
2
Tap out the problem
Digits and operations, big and readable — students follow every keypress from their seats.
Resize to suit
Corner-sized for quick checks, or huge for whole-class number talks.
Classroom ideas
Try it tomorrow
Three ways teachers actually run calculator — steal one for tomorrow morning.
Number talks, verified
Collect three mental strategies for the same sum, then let the calculator crown the answer. The strategies were the lesson.
Broken calculator
The classic puzzle: make 24 without pressing 4. On a board-sized display it becomes a spectator sport.
Real-world receipts
Price up the class party live — pizzas, juice, the works. A budget on the board beats a worksheet about someone else's shopping.
I model letters on the same dotted thirds they have in their books. The difference in their writing showed up within a fortnight.
Same dock, one tap away 
Pairs well with
Every tool lives on the same board — these turn calculator into a whole routine.
…and the rest of the dock is one tap away:
FAQ
Good to know
What can it do?
The essentials — add, subtract, multiply, divide. It's the classroom wall calculator, not a graphing lab.
Why not just use a desk calculator?
Because thirty students can't see a desk calculator. On the board, every keypress is part of the demonstration.
Can students use it?
Anyone at the board can tap away — great for checking their own working in front of the room.
Do I need an account to try it?
No — no login, nothing to install. Your board saves on this device; an account only matters for keeping boards across devices.
Put a calculator on your board
Open a board, tap the dock, and it's there. That's the whole setup.