What should i do about him?

maybe he can't skate so doesn't want to look stupid in front of you. Or maybe his friends would be really annoying and wolf whistle and stuff if he goes over to you so he didn't want to put you through all that. To be honest it sounds unlikely that he doesn't like you if he runs away, why would he run away if he had no reason to go near you, it's more likely that he just bottled it:) x