If you could go back in time, would any of us really want to be in High school again? Would you want to go back in time to when you were in high school knowing what you know now? Or would you just want to be a teenager again and attend high school now with all the technology? But then if you could just be a teenager, by going back physically, you wouldn't have the knowing what you know now? It's a conundrum I tell you, which explains why time travel will never happen.
But if you could go back, when would you go back to? I think I wouldn't mind the going back to high school, knowing what I know now. I sure would have had more fun and less worry, ending up in the same place.