Background: As part of our research programme into facilitating improved ways of communicating withpatients, especially about more sensitive clinical issues, we have been investigating whetherthere are any non-verbal methods that might aid this process. One such approach is to askpatients to choose a color in response to a particular question, for instance about health orpsychological status, and for this purpose we developed the Manchester Color Wheel(MCW). This instrument consists of positive, neutral and negative colors and its validation innormal adults and those with anxiety or depression showed that it is responsive to change andreproducible. It also has the capacity to identify a positive frame of mind. We concluded thatit might be a particularly useful instrument in adolescents and therefore this study aimed tovalidate it in a secondary school. Methods: 620 pupils (aged 11-17 years, mean age 14.0 years, 298 (48.1%) males, 322 (51.9%)females) at Sale Grammar School in Greater Manchester were asked to relate their mood to aMCW color and also complete the Hospital Anxiety Depression (HAD) questionnaire. Togive these pupils an experience in science, 197 were divided into four subgroups for anexperiment to ascertain whether, compared to controls, a change in mood color choicecould be induced by participation in sport, music or art activities. Results: Although mood color and HAD depression score are unlikely to be measuring exactly thesame psychological state, a negative mood color was chosen by 62.5% of HAD depressedcompared to only 14.5% of HAD normal pupils (p <0.001). In contrast, a positive mood colorwas chosen by 48.9% of normal and only 18.8% of depressed pupils (p <0.001). In theexperiment, compared to controls, all activities resulted in an increased choice of positivemood colors which reached significance for sport and music. Conclusion: This study confirms the potential utility of the MCW to rapidly and easily assess a variety ofhealth issues in large populations, including adolescents. Some of our results should also beof interest to educationalists.