There are traditions long associated with football games. Students growl like wildcats when the opposing team controls the ball, while simulating a paw with their hands. They will also jingle keys at the beginning of each kickoff. In the past, before the tradition was discontinued, students would throw marshmallows during games. The Clock Tower at the Rebecca Crown Center glows purple, instead of its usual white, after a winning game, thereby proclaiming the happy news. The Clock Tower remains purple until a loss or until the end of the sports season. Whereas formerly the Clock Tower was lighted only for football victories, wins for men's basketball and women's lacrosse now merit commemoration as well; important victories in other sports may also prompt an empurpling.

What do students traditionally do at the beginning of each football game kickoff?