You have a 10 minute speech to give at a high school, what is it about?

That every single student can be anything that they want to be. There are no restrictions - NONE. The key is in the management of their own daily, 24 hour clock. Nothing of value is ever really accomplished by sleeping, gaming, texting, MTV, or partying in excess.

To simplify, the time left over after your 8 hours of rest and 8 hours of school/employment will be the time in your young lives that will determine the quality of the rest of your life.