New Plymouth Boys' High School caters for day students and boarding students. The school runs a house structure with boys divided into one of four houses named after four famous Old Boys. The House structure is based on vertical grouping, with the three day-houses having 16 groups or huia rōpū and the boarding house (Hatherly) having eight huia rōpū groups.

Each huia rōpū has students from Year 9 to Year 13, with a teacher and student leader in charge of each group. Each house has a teacher as Senior Housemaster and a Year 13 student as Head of House. Depending on where in the alphabet the student's surname depends on which house they are placed in. For example, a student whose surname begins with M would be in Barak house. Each group has the first letter of their house (B, D or S) and a number, e.g. Barak 13 is called B13. The Huia rōpū meet twice a week before the day's first class. It allows the staff and senior students to provide pastoral support to the students.

Students start school at 8.40am, and finish the day after having five classes of 55 minutes at 3.10pm. The school ends early on Thursdays at 2.45pm to allow Sports and Cultural practice (SCP - during terms 2 and 3). The school runs a six-day timetable with each day of the week allocated a number, not a day. This allows the school to offer a broader range of subjects.

Every week parents and caregivers will be emailed on a Friday afternoon their son's engagement report. This will show your son's level of engagement and attendance for the last week, and a yearly average. The engagement report measures a boy's level of effort and engagement in class during the week and not academic progress. 

The Headmaster has one assembly a week in Ryder Hall on a Monday at 8.40am; this allows him to acknowledge the successes of students and outline his expectations of boys at the school.

Students of the school are expected to 'Be the Example' in all aspects of school life.