There's a lot of storytelling going on in the UK, quite a bit of it in schools, but it sounds as if Saul is in the US. To find out what's available, try using Google as there are several really useful sites with lots of stories and links to other stories as well as to storytellers, festivals, clubs and more. Mudcat tends to be more about music.
As to what sort of repertoire you should acquire, the only rock solid guarantee I know is that you should follow your own instinct as to what inspires you and what you feel most comfortable with. Trying to find out what appeals to youngsters is probably not the best way to go, as young people vary as much as older ones in what they like and in my experience they will be fascinated by a real person performing live in front of them and ready to listen more attentively than you might expect. I've worked in schools here in the UK as well as in the US and most of my experience has been with "difficult" kids, so I hope this is useful.