The outermost circle covers the content-based subject disciplines i.e. Languages, Humanities & the Arts, and Mathematics & Sciences. It ensures that students have a good grounding in content across different areas of study.

I think Definition 4 best fit to Singapore curriculum, where they have wide variety of knowledge and skills (thinking, process, communication etc..) to be learned, as well for humanities and arts, Languages, Mathematics and Science. However, in Singapore only IP students are offered a rich curriculum in social studies with alternative forms of assessment like project work and opportunities for social action so that they can be groomed for future leadership roles. (the elite Integrated Program (IP), the mainstream Express and Normal Academic track (E/NA) and the vocational Normal Technical (NT) track. Only the best students are allowed to join IP offered by 11 elite secondary schools. ) I think this alternative forms of assessment and opportunities for social actions shall be offered to all levels of students and not only elite students. In my opinion, all students has their own unique strengths, students who don't excel in academic doesn't mean they couldn't excel in other areas which they are good at.

Besides that, in high school learners are required to take subjects such as disaster readiness and risk reduction to prepare them for natural disasters and occupational hazards. The curriculum also allows students to develop their interpersonal skills among one another, which would benefit them greatly when they’re out of school.

Then the Ministry of Education (MoE) Brunei Darussalam then with SPN 21 which provided an educational system that prepares their young generation for future roles as capable, creative, thinking and innovative citizens who would uphold the local social values inherent in the national philosophy embedded in the Malay Islamic Monarchy or Melayu Islam Beraja (MIB) concept. The SPN21 Curriculum and Assessment Framework for schools includes critical skills in mathematics, science, languages and ICT; entrepreneurial skills and lifelong learning; and study skills and values education. Instead of just focusing on cognitive and skills development, other aspects of a holistic education such as the inculcation of spiritual, moral, social, cultural attitudes and values, as well as physical development, are given importance too in SPN 21.  This ensure the students spend their adult lives in a multi-tasking, multi-faceted, technology-driven, diverse and vibrant world, and they must be equipped to do so. 

The curriculum under SPN 21 make sure on bring the best out of students in the school system and beyond when they enter the world of work. It allows highly capable students to complete their secondary education in a shorter period of time (four years). This benefits the nation in its efforts to optimize human resource development. This is enshrined in its policy of providing every student with at least 12 years of learning experiences. An increase in the number of students joining technical education is also anticipated. This reduces the problems of early attrition among students, as well as provide more time to nurture students to become more mature individuals before they leave the school system. The SPN21 structure (see figure below) provides multiple pathways for students to choose programs that suit their capabilities, interests, inclinations, growth and development; thereby catering to their needs. 

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