Fun activities, places to go in SF that I may not have explored yet?

I love my San Francisco life, but realize that there is so much here I am not taking advantage of. I tend to stay in the same neighborhoods and go to the same bars and restaurants. I live in one of the most amazing cities in the world. What am I missing? I want to try something new in my own backyard! It can be restaurants, museums, activities, secret nooks, etc. What have you discovered to be a hidden (or not so) gem of our gorgeous city? For example, I have never been to the Exploratorium but I bet it’s a blast for a day.