Answer:
I am black within and red without; with four corners round about. What am I?
You write on me and secrets I can keep in places never seen. I spin like a top. Though stiff as a board, I'm often described like a mop. What am I?
I'm really blue but when you see me I'm red. You don't see me too often. I'm there for you if you're hurt.
I come in different colors and shapes. Some parts of me are curvy some are straight. You can put me anywhere you like but there is only one right place for me.
I am a path between high natural masses; remove the first letter to get a path between man-made masses.
What made Cyclops quit teaching?