It’s time for March Madness, and college basketball fans are excited about the NCAA Tournament, so it’s a perfect time to learn about the graph theory version of tournaments.  In my talk, I will prove the formula for the Vandermonde determinant using a sign-reversing involution on a particular set of tournaments.  I will also use a similar technique to prove a formula that relates the Pfaffian, which is an analogue of the determinant, of a skew symmetric polynomial with the Vandermonde product.