Here is a list of places to visit eat and shop
How about Niketown or the Jets shop? Will you be in Manhattan for the draft? (I assume it will be in Radio City Music Hall again, did not check).
No idea if this would appeal to a 15 yo boy but Blue Man Group is considered 'cool'
But stay away from Guy Fieri's new Times Square restaurant it is supposed to be horrible.
Maybe this will get you started anyway