See the NCTM Illuminations site for a fun middle school activity that uses baseball stats, to help students better understand independent events in probability.
The following grades 6-8 activities allow students to explore statistics surrounding baseball. They are exposed to connections between various mathematical concepts and see where this mathematics is used in areas with which they are familiar. This lesson plan is adapted from the May 1996 edition of Mathematics Teaching in the Middle School.
More details at: http://tinyurl.com/8xgexvy