Her reputation for turning around underperforming classes quickly spread. Within five years, she was promoted to head of the English department at a major government secondary school. It was during this period that she began experimenting with bilingual teaching methods, recognizing that Singapore’s future depended on citizens who were fluent in both English (the language of commerce) and their mother tongue (the language of cultural roots).
Nellie Tan Li Koon passed away peacefully on March 12, 2015, at the age of 85. Her funeral was attended by hundreds of former colleagues, students, and policymakers. In her eulogy, then-Education Minister Heng Swee Keat said: "She taught us that education is not a product to be manufactured, but a relationship to be nurtured." nellie tan li koon