Athletes at all ages are bigger and stronger than ever before. And they are being encouraged - sometimes even incentivized, as we recently learned was the case on at least one National Football League team - to play to injure.

My children have been learning lessons about entrepreneurship since they were in kindergarten, and these lessons are paying off: even though they are only 22, 18, and 15, they have already collectively launched three nonprofit organizations and several new businesses.

What separates sports from entrepreneurism, however, is that in business we constantly have to overcome undefined and unpredictable challenges. Athletes train for specific events and conditions, whereas entrepreneurs generally have little idea what they will encounter along the way.

Because I was poor I had one special advantage. When you are poor, and basic survival is your concern, you have no alternative but to be an entrepreneur. You must take action to survive just as you must take action to seize an opportunity.

Education should not be about building more schools and maintaining a system that dates back to the industrial revolution. We can achieve so much more, at unmatched scale with software and interactive learning.

Sometimes a faint voice based on instinct resonates far more strongly than overpowering logic.

Don’t wallow in brainstorming. Time spent fiddling with a business plan or filling up whiteboards with ideas is time that you could spend actually launching your business and seeing if the idea floats. Launching gives you real, solid feedback, instead of the imaginary “what if” scenarios dreamed up in a conference room.