The FPS was established to examine factors associated with the onset and course of mental health conditions during adolescence. The study was launched in 2019 and involves working with over 6,000 students aged from 13 to 18 from 134 schools around Australia over a 5-year period. Recruitment for the study occurred between March 2019 and March 2022. At baseline, study participants were in Year 8, with a mean age of 13.9 years. Most students (85.6%) attended schools located in New South Wales, the same state as the study team. Participants mostly identified as female (48.9%) or male (46.5%), with 4.5% indicating that they were nonbinary, other, or preferred not to say. Most participants were cisgender (94.2%) and 3.2% were gender diverse (participants whose gender identity was incongruent with their sex at birth).