Answer:
I build up castles. I tear down mountains. I make some men blind, I help others to see. What am I?
What force and strength cannot get through I with my unique teeth can do.
What can you catch but never throw?
I am enjoyed by some despised by others. Some take me for granted some treasure me like a gift. I last forever unless you break me first.
I can climb mountains, cross streams, handle hundreds of feet each day, yet I never move. What am I?
Before I grow I'm small. When I'm old I grow tall. When I die I give a mighty fall.