i have to do, and just on a human level, water is another thing that's important to me because -- teterhe most basic of needs and to know that so many millions of people today, right now, still don't have water, like -- it's like one on the list, it's like water, it's like -- sad, you know, and on a human level, everyone should have access to water, i mean, we all believe that, and so just opportunity in life. >> charlie: congratulations on this book. >> thank you. [applause] >> charlie: the book is "jay-z decoded," that's what we have been talking about, we're at the brooklyn museum talking to a young man. [applause] >> charlie: who came out of brooklyn to make extraordinary music, to make a difference. and i am pleaseded to call him a friend. thank you, jay-z. >> thank you. thank you, man. ♪ captioning sponsored by rose communications captioned by media access group at wgbh access.wgbh.org ♪ ♪

. >> this is teter. very strong, be careful walking across this, it is a rope bridge.lywood floor. you can see the stairs to the top floor there? >> reporter: so we're not even on the top floor yet. >> this is where you can see everything and anything. i'm not exactly a huge fan of heights. >> reporter: we're 60 feet high, we're on the floor of your newly build tree house and now you're telling me you're not a big fan of heights, are you nervous being here? >> not really because i know it's built well. >> reporter: but you're still afraid of heights? >> yes. >> reporter: alex is only beginning to grow into his tree house, much like the folks who show up at pete's workshop. and attend of the day, when the tool belts are put away, they're all just kids who love hanging out in trees. >> i have to remind myself sometimes that i'm a tree house builder, every time i think about it, i think, wow, i'm a lucky guy. i had this idea that i wanted to be the tree house guy. i mean why not? >> by the way i asked peter if he would consider building something, something in the rockefe