The aim of the present study was to establish the efficacy in terms of morbidity and health-related quality of life (HRQoL) of a group asthma education-exercise programme to children with low (below 10th percentile value) quality-of-life scores. A controlled, randomised, open, clinical trial was conducted. In total, 36 out of 53 unhappy children, among 204 (68%) respondents, treated in four paediatric practices, enrolled (mean age 10 yrs; range: 8-12 yrs), after random allocation in control and intervention groups (child, parent, teacher). Measurements were taken at baseline (T0) and after 3, 6 (T6) and 9 months (T9; intervention group only at 9 months). All but four controls completed the study. From T0-T6, changes (Δ) in HRQoL were clinically important and significantly greater in the intervention group than in the control group, both for generic HRQoL (effect size (ES) 0.95; Δ 16% ± 12% versus -1 ± 4%) and for asthma-specific HRQoL (ES 0.58; Δ 15% ± 17% versus 1.5 ± 14%). T9 measurements were consistent with T6 findings. Changes in sick days (ES 0.78), oral prednisone courses (ES 0.71) and doctor visits (ES 0.74) over a 6-month period were greater in the intervention group than in the control group. Changes could not be ascribed to change in lung function or medication. In unhappy children, quality of life and morbidity may improve with a low intensity asthma education-exercise programme, even without gains in pulmonary function or exercise tolerance. Copyright©ERS Journals Ltd 2008.