Build it gradually
Reveal one position at a time, focus the selected key, or show the complete classroom poster.
Free classroom board
Circle of Fourths
Start with one key. Build the relationship.
A projection-ready board for teaching major keys, key signatures, relative minors, and the same circle viewed as fourths or fifths.
Made for the room
Teach the relationship, not just the diagram.
Turn the circle around
Switch between fourths and fifths without changing the underlying key relationships.
Connect the layers
Add written signatures, accidental counts, relative minors, keyboard paths, and accidental order only when the lesson needs them.
Practice on the bars
Select a key and see its major scale on a piano or xylophone-style keyboard, with optional scale-degree roles.
Share the setup
Copy a lesson link that restores the board’s direction, mode, selected key, revealed positions, and visible layers.
Print what students need
Download US Letter, A4, and 11 × 17 posters, or turn the same material into student and answer-key quiz views.
One board, several uses
From first reveal to independent recall.
Teacher-led display
Use Build mode for a progressive explanation, Focus mode for one key, and Present for a clean full-screen board. The teacher controls the pacing; the app records no student data.
Printed follow-through
Keep the standard poster visible, print a focused board for a binder, or prepare a quiz that asks for key names, signatures, or accidental counts.
- Build
- v0.15.0
- Account
- None
- Cost
- Free
- Privacy
- No student data collected
Put the circle on the board.
Start with one key, then let the relationships appear.