http://en.wikipedia.org/wiki/Jedi_Training_Academy
Basically Jedi Masters teach about 30 to 40 kids how to use lightsabers and be good Jedis in the Force, when suddenly Vader and Darth Maul appear and each kid gets to individually fight Vader or Maul.
What makes the show so great is that each kid has their own reaction to being up on stage and fighting Darth Vader and Maul. Kids get up there and are totally into it and do their moves perfectly to the teaching, other times the kid just starts wailing away, and the best is when a kid gets up there and just freezes in awe

It's so much fun watching the kids get up there and having a kind of once-in-a-lifetime experience and it's probably something they'll remember for the rest of their lives. My wife and I always catch at least one showing every time we go to the park, and it's always one of the most entertaining parts of our day. It's great fun watching all the kids be so happy and into it, and especially overhearing them afterward (usually you'll hear things like "I got to fight Darth Maul!" and "Dan's going to be so jealous!").
I highly suggest everyone watch at least one show of the Jedi Training Academy - especially if you have kids. It's one of the great things in the park that is completely free and your child will most likely remember for the rest of their lives
