This study aims to examine the effectiveness of musical training in promoting happiness and quality of life of preschool children from low-income families.

Participants in the experimental group will attend a weekly 1-hour musical training lesson for 12 weeks conducted by the Music Children Foundation. While participants in the waitlist control group received the same training after the experimental group had completed the intervention.

Children from low income families generally suffer from hard conditions,such as poor living conditions, inadequate nutrition, and delay in accessing health care services. Such problems may made children suffer from developmental problems and malnutrition and to have a lower level of intelligence and difficulties in language comprehension, which may not only have profound impacts on children's physical well-being, but on their psychological well-being as well. Musical training is considered to have potential for promoting psychological well-being among children mostly because music is found to be important to a child's early psychological development. A growing number of educators and researchers suggest that, of all the stages of life, infancy may be the time when music has the most important impact on an individual. Babies hear language long before they are able to comprehend it. The quality and the quantity of what is unconsciously absorbed in infancy relates directly to later development. Musical training has been used for various purposes such as improving language development, self-expression, memory skills, concentration, social interaction, fine motor skills, listening, problem-solving, teamwork, goal setting, and coordination. More importantly, when a child learns to sing and play music, other areas of development - creativity, family bonding, self-esteem, confidence, emotional development - are also positively impacted.

Nevertheless, although musical training is popular and is considered to be a beneficial intervention in the promotion of psychological well-being, longitudinal studies that examine the efficacy of music-making in children from low-income families are limited. Importantly, there is to date no study that examines the effects of musical training on enhancing the psychological well-being among these children. There is an imperative need for rigorous empirical scrutiny of the effectiveness of musical training in promoting the psychological well-being of children from low-income families. Therefore, the aim of this study is to examine the effectiveness of musical training in promoting happiness and quality of life of preschool children from low-income families.

Inclusion Criteria:

• be aged from 3 to 6 years,
• be able to communicate in Cantonese,
• be from low-income families; that is, less than half the median monthly household income or recipients of Comprehensive Social Security Assistance.

Exclusion Criteria:

• children who had studied or were studying (at the time of the intervention) a musical instrument
• children who were receiving other community services at the time of the intervention,
• children with chronic illness or identified cognitive and learning problems.