They are sturdy, purpose-built boxes that will last for up to eight years in the wild, 10 if they are installed in a sheltered position.

The students, under the guidance of their teacher, Mr Ralf Hansson, build these boxes every year for Wildcare, the wildlife rescue and rehabilitation group for our area.

The project is appreciated by students as they see their work actually being utilised in the community.

It is appreciated by the school because it fits neatly into the senior syllabus and because Yass High has a long tradition of community involvement.

Why are these boxes needed?

Every year adolescent possums come into care because once they have left their mother for their own lives they are unable to find accommodation that is not already occupied, especially in urban and near urban areas.

There are simply no more old trees with holes capable of housing a possum.

These boxes allow a released possum a home of his own, which he may occupy his whole life or which may become a home for some other juvenile when he is big enough to sort out a territory and a tree hole for himself.

Invariably, even years later, when carers check these boxes there is always a possum in residence.

"Until four years ago we had difficulty sourcing boxes for our possums on anything but an erratic basis," said Wildcare spokesperson, Kevin Baker.

"Since Yass high has been involved, we have this regular well-built supply which we value tremendously, and we are very grateful to the students and Mr Hansen for making this possible."