Control of error is the feedback built into a Montessori material or activity that lets a child notice and correct their own mistake, without an adult pointing it out.
Examples
| Material | How the error shows itself |
|---|---|
| Knobbed cylinders | Each cylinder fits only one hole. If one is misplaced, the last cylinder won’t fit. |
| Pink tower | A cube out of order makes the tower look wrong or wobble. |
| Pouring with two jugs | Spilled water on the tray shows the pour went off course. |
| Puzzle maps | A piece in the wrong place doesn’t fit. |
| Math work | Answer cards or a control chart the child checks after finishing. |
Why it matters
When the material shows the mistake, the child stays in charge of the work. They try again because they want it to work, not because an adult said it was wrong. Montessori saw this as the basis of independence and of a calm relationship with mistakes.
The adult’s part
Don’t correct a mistake the material will reveal. If a child repeatedly misses it, show the activity again another day, slowly, without mentioning the error.
At home
Choose activities with a visible result: a puzzle with one place per piece, pouring over a tray, matching socks into pairs. Related: didactic materials and autoeducation.
Common misunderstandings
- “Errors should be avoided.” In Montessori, an error the child discovers is part of learning, not a failure.
- “It only exists in classroom materials.” Everyday life has many: a spill, a sock without a pair, a door that won’t close.
Questions parents ask
What is an example of control of error?
The knobbed cylinders: each fits only one hole, so a misplaced cylinder leaves another one without a place.
Should I correct my child’s mistakes?
If the activity will show the mistake, wait. Present the activity again another day if needed.
Sources
- Montessori, M. The Discovery of the Child (1948), on the control of error in the materials.
- Montessori, M. The Absorbent Mind (1949).