Best hard riddles for teens

A man is found hanging in a room 30 feet off the ground. There is nothing else in the room except for a large puddle of water on the ground. The police can't see any way the man could have climbed the walls to get to where he is hanging. How did this man hang himself?

I am a five letter word and very strong. I become single when you remove two letters from me. What Am I?

What goes up but never comes down?

You are in a cabin and it is pitch black. You have one match on you. Which do you light first, the newspaper, the lamp, the candle, or the fire?

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

What happened when wheel was invented?

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 is bigger: Mr. Bigger, Mrs. Bigger, or their baby?

What do you get when a turkey lays an egg on top of a barn?