* Definition of "poor motor skills" varies: What constitutes "poor" is subjective and depends on the specific assessment used. Different professionals (teachers, therapists, etc.) might have different thresholds. Some children might struggle with fine motor skills (writing, drawing), while others have difficulties with gross motor skills (running, jumping, balance).
* Lack of standardized, widespread screening: While some schools conduct developmental screenings, there isn't a mandatory, nationwide (or even country-wide) system for assessing motor skills in all children of this age group.
* Prevalence varies by factors: The percentage of children with motor skill difficulties likely varies based on factors like socioeconomic status, access to healthcare, nutrition, and pre-existing conditions.
While studies exist on the prevalence of developmental coordination disorder (DCD), a condition characterized by significant motor skill challenges, these studies provide prevalence rates, not necessarily a direct answer to the percentage of children with *simply* "poor" motor skills in school as perceived by teachers. Even DCD prevalence rates vary across studies.
In short, it's impossible to give a reliable percentage without a much more specific definition of "poor motor skills" and access to data from a large-scale, standardized assessment. Any number you might find would be a rough estimate at best and potentially misleading.