There are a few steps schools can take to help parents understand that their child’s behaviour is beyond the range for normal. If the class has a one-way mirror for observations, this could be used, perhaps someone being with a child and pointing out inappropriate behaviour. Observing from a visible observation window can be scheduled. Observation can be helpful if the behaviour is occurring in the workings of the class. If the challenging behaviour occurs when children are outside playing, documenting situations in which the behaviour becomes challenging can be noted—over a period of two or so weeks.
Observation and journalling is followed by a discussion with the parents, explaining concerns, showing the journal of concerning behaviour.
If the child is an only or first child, the parents may not be aware that their child’s behaviour is challenging, or beyond what is socially acceptable.
This might also be a stimulus for a school to check their enrollment contract to determine the boundaries under which the family/school is co-existing. In said contract somewhere it should be noted that the needs of some children may not be manageable in the Montessori setting.
The child’s teacher should keep a daily journal of situations that evoke challenging behaviour, the child’s reactions, the adults’ response.
Final step would be the school requiring an outside evaluation and suggestions for modifications.