Winona LaDuke

Executive Director of Honor the Earth

Former MythBusters Build Team: Tory Belleci, Kari Byron and Grant Imahara

MythBusters Build Team: Tory Belleci, Kari Byron and Grant Imahara

Anna Escobedo Cabral

Former Treasurer of the United States, Partner at The Cabral Group & Jesse Ball duPont Fund Trustee

Noah Galloway

U.S. Army Veteran, Amputee & Finalist on "Dancing With The Stars"

Diane Rehm

Radio Talk-Show Host

Tom Silva

General Contractor, Member of Home Improvement Team on "This Old House"

Delvin Choice

Top 8 Finalist on Season 6 of NBC's 'The Voice'

Lance Gross

Actor, Model & Photographer; Best Known for "House of Payne"

Ali Vincent

First Female Winner of "The Biggest Loser"

David Williams

Professor of Public Health at Harvard University

Bill Kurtis

TV Journalist, Producer, Narrator and News Anchor; Host of A&E's "Investigative Reports," "American Justice" and "Cold Case Files"

Katie Stevens

Actress & Singer Known for "The Bold Type"

Fonzworth Bentley

Musician, Author and TV personality; MTV's "From G's to Gents"

David Banner

Rapper, Record Producer, Activist & Actor

Phil Simms

CBS NFL Lead Analyst, Super Bowl MVP, Co-Host on Showtimes "Inside the NFL"

Jeremy Heimans

Co-Founder & Chairman of Purpose; Best-Selling Author; Lifelong Activist & World-Renowned Expert on Building Social Movements

Robert Putnam

Professor of Public Policy, Harvard Kennedy School of Government; Author of "Our Kids"

Anthony Atala

Director, Wake Forest Institute for Regenerative Medicine

Brian Kilmeade

Television & Radio Presenter; Co-host of "Fox & Friends" on FOX News Channel

Josh Radnor

Actor, Filmmaker, Author & Musician Best Known for his Role in "How I Met Your Mother"

Choosing Between Growth or Depth As A Man - Josh Radnor