I am surprised that in various countries, whether it's the U.K. or the U.S., you see isolationist tendencies that would tend to work against the co-operation, whether it's climate change, immigration, innovation, helping the very poorest. Those are things where you want to think across country boundaries and see a win-win-type solution.

In ninth grade, I came up with a new form of rebellion. I hadn't been getting good grades, but I decided to get all A's without taking a book home. I didn't go to math class, because I knew enough and had read ahead, and I placed within the top 10 people in the nation on an aptitude exam.

Scientists and companies weren't creating things like new vaccines. Now that we have this fund that's there to buy at the lowest price, but buy for those people these medicines, we see scientists everywhere coming up with those new tools.

Embrace bad news to learn where you need the most improvement.

I think we knew that this would be just like raising the kids together, this would be a fun thing to do in partnership. And you know, we're so lucky because we get to hire in very smart people. We get to partner with governments like the Canadian Development Organization - CIDA, USAID - tonnes of scientists doing this work. This is fascinating.

Teaching's hard! You need different skills: positive reinforcement, keeping students from getting bored, commanding their attention in a certain way.

In the old generation, if one kid bought a PlayStation 2 and the other kid bought an Xbox, at his house you played PlayStation, at your house you played Xbox. Now that it's online, all those early buyers who... you want to play with, they've got their reputation online of who they are and how good they are at these games.