When the children had completed an absorbing bit of work,
they appeared rested and deeply pleased.
—Maria Montessori (author), Paul Oswald (editor),
Basic Ideas of Montessori’s Educational Theory
Children as young as three-years-old, after several months in a Montessori classroom, are able to choose their own work and focus on and finish their tasks. Through observation and experimentation, Montessori discovered the importance of a two-and-a-half to three-hour uninterrupted work period. The last hour of a lengthy work period is usually when children are most likely to choose challenging work and concentrate deeply.
Montessori once observed a three-year-old repeat the knobbed cylinders activity 44 times. The girl’s concentration did not waver when Montessori tested it, first picking up the girl in her chair and placing her (still in her chair) on top of her desk and then asking classmates to sing. When she stopped working of her own accord, “…she looked round with a satisfied air, almost as if waking from a refreshing nap.” Montessori called this a “never-to-be-forgotten” discovery. (Spontaneous Activity in Education)