Year 10 Term 4 was depressing... it was going to summer and it had that 'end of year feel'. Then you had people start to leave, so in our cohort of 60, you had 55, and then 50 progressively. We then had a Year 11 Orientation day - there was about 25 of us. Whole groups would not turn up anymore, and it was really... awkward and sad in a way. You go around and think, "Is this it?"
Like for example, this girl got an award at Presentation Night. But because she and her friends decided to bludge (as they were going to another school the next year), she came to Presentation Night in casual clothes and could not receive her award.
tl;dr It's a bludge.