A compass, like scissors, tweezers, glasses, pliers, tongs, bellows, and calipers, is an instrument that is made up of two near-identical pieces that are attached to each other. Comparing it with these examples, it's somewhat surprising that we generally refer to it in the singular rather than in the plural. All three constructions: a compass, a pair of compasses, and compasses, are acceptable, although a compass is currently the general usage.
So if compass is used in school, and it is a directional flight implement, then I dont see how anything else will be the answer.
In which case the only thing that is wrong is the number of letters, and in the past this has sometimes found to be the case.