This quick little activity is constantly requested in my studio. It's just the thing for students who need a little brush up on sharps and flats.
Stack up the Ewe Cards and have your student name and play each note on the piano. It's fun if the ewe jumps over the fence with each correct answer. Be on the look-out for enharmonic equivalents, that's when F sharp and G flat appear in sequence. In my studio, if an enharmonic equivalent shows up, the student gets a jellybean.