I think Scripps Ranch HS is packed. Also Poway HS is much closer to Stonebridge then Scripps HS. As I said I believe another high school is being built but it is at the far west end. Also I “heard” that there are going to allow students from Mira Mesa to go there as well. This is unreliable at best, not checked out with the SDUSD or anything like that.
Again don’t know why Stonebridge kids go to Poway but it makes alot of sense.