In all bilingual communities providing children with appropriate language instruction is a very important issue for governments, educators, schools and finally language learners themselves. Due to contradictory results of studies concerning the association between bilingualism and cognitive functioning, it is very important to develop bilingual skills that will contribute to cognitive performance and, thus, will help students to achieve academic success. In Hong Kong, where being bilingual or trilingual has always been a competitive advantage, it is especially important to raise language skills of individuals and, thus, enable them to meet the needs and challenges of the society. Educational policies play a crucial role in developing additive bilingualism, which allows students to develop proficiency in a second language and maintain a high level of a native language at the same time. Thus, the government together with the Standing Committee on Language Education and Research (SCOLAR) has adopted several education policies reforms aimed to raise language skills in the community of Hong Kong.
The term bilingualism has been defined in several different ways by researchers and theoreticians (Cummins & Swain, 1986). While some authors classified different kinds of bilingualism according to the age at which second language (L2) was learned (early versus late, simultaneous versus sequential), others considered such factors as the contexts of language learning (artificial versus natural, compound versus coordinate) and the domains of its use.
Later studies confirmed these findings and showed that bilingual children had relatively low literacy skills (children of Finnish migrants in Sweden), arithmetic competences (English-speaking children educated in Irish-medium schools), vocabulary levels (low class Spanish-English children) and general verbal and academic skills (English-Japanese bilinguals in the United States) when compared with unilingual children.