the JDC Challenge  consists of 3 parts

Part 1: Shanghai 10-15:3 darts at each number in turn socring only on that number. (i.e. S10, S10, T10 = 50 Points)
If you hit shanghai (T, S, D) you score a Bonus of 100 Points

Part 2: Round the World Doubles: One dart at each double in turn. i.e. one dart at 1, one dart at 2, onde dart at 3 and so on round to the bull. Scoring 50 Points per double hit and 100 points for hitting the bull

Part 3: Shanghai 15-20:3 darts at each number in turn socring only on that number. (i.e. S15, S15, T15 = 75 Points)
If you hit shanghai (T, S, D) you score a Bonus of 100 Points

JDC average score indicator:

White Shirt Beginner 0-150
Purple Shirt   150-300
Yellow Shirt Improver 300-450
Green Shirt League Standart 450-600
Blue Shirt League Division 1 Standart 600-700
Red Shirt Super League Standart 700-850
Black Shirt County Standart 850+

 

 (source: www.juniordarts.com)