Answer:
What goes around the wood but never goes into the wood?
I'm where yesterday follows today and tomorrow is in the middle. What am I?
I'm light as a feather yet the strongest person can't hold me for more than a few minutes. What am I?
I am used when you jump off a bridge for fun.
I am the kind of soda you must not drink. What am I?
No matter how little or how much you use me, you change me every month.