Hard logic riddles for teens with simple answers

What is black when you buy it, red when you use it, and gray when you throw it away?

Mr. Jason was walking along the sea shore. Suddenly it started drizzling and turned into a heavy rain. He wasn’t carrying any umbrella, not even any cap. He was completely wet and all his clothes were soaked in rain. Yet not even a single strand of his hair was wet! How was that possible?

A slender body, a tiny eye, no matter what happens, I never cry. What am I?

What has two hands and face but no arms and legs?

I can run, but not walk. Thought is not far behind me. What am I?

Physicists have built devices to move me very fast. My last seven letters can be commonly found in newspapers, magazines and journals. What am I?

I am a 5 letter word. Take away the first letter and I am a country's name. Take away the first two letters and I become the opposite of the 5 letter word. Who am I?

Who makes it, has no need of it. Who buyes it, has no use for it Who uses it can neither.

Thirty white horses on a red hill. First they champ, Then they stamp, Then they stand still. Who are they?

If you drop me I'm sure to crack, but give me a smile and I'll always smile back.