Answer:
I am in the past, never in the future. I don't exist, but have existed. I saw what you saw, and this is what I will ever see. What am I?
Send poorly behaved children to me and let them sit here. What am I?
I am tomorrow's yesterday and yesterday's tomorrow. What am I?
I have thirteen hearts but no body or soul. What am I?
I am so delicate that even mentioning me breaks me. What am I?
What do you purposefully put lots of in and on your body, but run away from when you encounter it outside?