Mr Wheeler said the pupils, ranging in age from 5 to 11, had brought all the materials for their shelters after viewing photographs and video clips of the aftermath of a string of disasters - floods, earthquakes, tsunami - that have struck the Solomons in past weeks.
Assistant principal John Murray said the unit on the Solomon Islands had begun about six weeks ago before the floods and earthquake struck and the Caritas exercise had been in focus for the pupils over the past fortnight.
He said pupils had been working in small planning groups "to find out what they need" and the fine weather had been a happy accident.
"What they've been finding out is what materials are suitable and what aren't and that their plans keep changing. What we also wanted the kids to find out was being inside the shelters and having their lunch in a confined area, to just get a sample of what people's lives are like in the Solomons, so they can get some empathy with other people around the world."