A study conducted in Taiwan (2009) collected data simultaneously on emotion, physiology, cognition, behaviour, and health, using both subjective and objective measures, to find if having plants in the classroom had effects on the mood, behaviour and health of the students. Two classes were compared, one of which had plants placed in the back of their classroom, and one of which had not. In addition to questionnaires that were surveyed every other week for one semester, a total of 10 responses per student, their examination scores, sick leave hours, and punishment records due to misbehaviour were also recorded.

The study found, that the classroom with plants had:

• an immediate positive influence on perceptions of preference, comfort, and friendliness of the classroom
• classroom vegetation had positive effects on students’ health and behavior

Experimental group had fewer sick leave hours (2.149) than control group (5.984), with a statistically significant difference (p<0.001). Fewer punishment records due to misbehaviour were also recorded with plants (0.015) compared to without plants (0.522) with a statistically significant difference (p<0.025).

This study supports the earlier theories that contact with nature has benefits on human health and well-being on many levels.