Make sure the student understands a) that because the markings he reads are the ones facing him, the north-seeking edge of the compass is actually the one with the "S" marked on it, and b) that because the lines of magnetic force go around the earth and into the pole and out of the poles that the north seeking end of the compass is being pulled both north and down (up in the southern hemisphere).
Now balance a small bowl upside down on the eraser end of a pencil. Accelerate the pencil forward. Observe which way the bowl tilts. If you think of the part of the bowl with the "S" on it being pulled upward or downward, as appropriate to your hemisphere, you will see that if the plane is flying on an E-ish or W-ish heading the bowl will turn.