an abstract piece in unconventional non-traditional materials
All I did was break the wording down a bit, and basically you need to make an abstract piece. You should pretty much know what that is.
Think of what it means unconventional, and non traditional. What are traditional materials that are used in are. Traditional meaning, like the usual, paint, clay, etc. So for unconvential and non traditional, it means you should be using something that is not usual art materials or stuff you wouldn't gater at an art store. Coffee, blood, rope, trash, etc. Mix media.
unconventional non-traditional materials : I think it's to art related material, so I would understand it as making an abstract creation with non artistic materials. An example in the art history is Dali shooting at metal plates with an old rifle. What I imagine right now : You can glue pieces of old tires on a support to create a shape. Place a large paper sheet at an entrance to have the many foot prints of people passing here. Make an abstract creation of rubber band on glass.
Try googling mixed media art instead I suppose they mean something like collaging different materials (from papers, photos, etc. to pieces of cloth, lace, feathers, CDs or any lightweight objects usually not used in art), to a thick support (canvas, thick cardboard or wood).