The Teacher--Learning Idioms from BBC Learning English

A section of BBC Learning English, The Teacher,teaches idioms in an interesting way.  You will watch a video, in which the teacher introduces three idioms at a time in an interesting way.  What's more, on the same page, you can see several passages created by learners from all over the world using these three idioms.

http://www.bbc.co.uk/worldservice/learningenglish/language/theteacher/index.shtml

Click on the following link to see an example, in which all the three idioms contain the word "ball"--keep your eye on the ball, it's a whole new ball game, on the ball.  Guess the meanings of the idioms before you watch the video.  The first two may be easy.  How about the third one?

http://www.bbc.co.uk/worldservice/learningenglish/language/theteacher/2009/08/091008_teacher_sport_balls.shtml