This research examines how Tongan family structure affects the academic performance of students at the secondary level of education. It is a comparative study with the aim of examining whether there is a significant difference between the academic performance of students raised in a traditional family and those students who were raised in a non-traditional family. A Tongan traditional family is defined as comprising two biological parents (or adoptive parents from birth), one male and one female. In contrast as non-traditional family may be a single parent family (including by birth (solo-mother), divorce or death), or the student has no parent present (for example they are staying with relatives or friends). In this study I am looking at what are the key drivers of success and trying to understand the relationship between academic performance and family structure. I hope that empirical evidence will assist the Tongan school administrators, other educators and parents to adopt the best practices and actions for their students’ academic achievement. The target population for the current study is the secondary school students, age 13 to 18 years in Tonga in the main island of Tonga- Tongatapu which has 13 secondary schools. Two secondary schools are government schools and the others are private schools run by different religions. From May 23rd to 2nd of August 2017, I surveyed 360 students, 60 from each of 6 selected secondary schools. Unfortunately two schools had to be excluded from the analysis. The results presented here are of 4 schools with 240 participants. This is the first study to be conducted in Tonga. Students’ performance scores on the internal assessments of each school were assessed using multiple linear regression and an ensemble of different model selection methods. Findings indicated that students’ family structure has a significant effect on their academic performance. The study has identified that the most key drivers for academic success are, in order of importance, school, parental involvement, family structure, age, family expectation and family religious status.