In case you are interested in Fact Sheets, past draws, etc. please go to this this and surf a bit.
Other than all three tournaments being prestigious and of a high standard, the main draws of the two younger divisions act as qualies for international team competitions - the Junior Davis Cup for 16s and World Junior Tennis for the 14s. There was a time when we had one for the 18s, too - the Sunshine Cup, but the USTA and ITF have stopped that for no reason at all.
Captain is Rusedski, again. Lucky kids! Getting a just retired former Slam finalist as your mentor and hitting partner is something most players can only dream of. Hopefully they'll make good use of the experience.