Greendale Secondary School opened its doors to the first intake of 320 Secondary 1 students on 2 January 2006. The school derived its “green” from Punggol’s rustic, green and waterfront living setting, with “dale” providing a link to its location at Edgedale Plains. The school was officially opened by Dr Teo Chee Hean, who was then the Minister for Defence, Minister-in-charge of the Civil Service and MP for Pasir-Ris Punggol GRC, in 2007.
In 2005, the Principal Mrs Mary Koh together with a selected pool of experienced HODs and Teachers, set about to prepare for the establishment of a new secondary school in Punggol. In 2006, Greendale Secondary School took in the first batch of Secondary One students.
In December 2008, Mr Mark Gerard Minjoot took over as Principal of Greendale Secondary School. Greendale Secondary School aspires to be a premier school in the north-east. In the last few years, the school has attained some outstanding results in both the academic and co-curricular areas and is gaining a reputation for providing a value-added, holistic education.
In December 2014, Ms Amy Ng joined the school as its current Principal. Tapping on the school's achievements and strengths, and with the support of various stakeholders (students, staff, parents, school advisory committee, alumni), Greendale Secondary School's journey to become a School of Choice that Makes a Difference: Home of Committed Learners, Critical Thinkers and Confident Leaders continues.