Answer:
I can be written, I can be spoken, I can be exposed, I can be broken. What am I?
Taken from a mine and then locked up in a wooden case. I am used by students everyday.
What has a head and a tail but no body?
I'm not alive but I grow I don't have lungs but I need air I don't have a mouth but water can kill me. What am I?
I am round. I have only one line. Circle is not my name indeed. What am I?
What do you purposefully put lots of in and on your body, but run away from when you encounter it outside?