The four members of our Executive Team have over 50 years combined experience in NSP, equipping students as leaders for Christ.  

  • Warren Willis

    CEO & FOunder

    Warren Willis has over 55 years of experience in gospel outreach at home in the United States and abroad.  His ministry journey began in the 60’s at UC Berkeley with Campus Crusade for Christ. At the time, the Berkeley campus was known for being anti-establishment, and Warren witnessed to 199 people before a single person came to faith in Christ. After 39 years, with assignments at Berkeley, Micronesia, Canada, the Philippines, and Mongolia, Warren has helped thousands of people come to Christ. 

    When Warren returned to the US, he was shocked to see the irreligious state of the public schools. Convicted, he founded the California School Project at Biola University in 2002, with the goal of training college students to mentor Christian students at public high schools in the area to reach their peers with the gospel. The ministry expanded steadily and is now known as National School Project: operating out of ministry hubs in California and Illinois. 

    He continues to lead and inspire NSP to reach every public school in America.

  • Mark Hopson


    Mark Hopson has been with NSP for fourteen years, beginning in 2003 as a Campus Mentor while attending  Biola University. After graduating in 2006, he joined NSP full-time as a Chapter Director for the greater Los Angeles area and served in this position for seven years during which time he received an M.A. in New Testament from Talbot School of Theology.

    In 2013, Mark moved his family to Chicago, IL, to start three new ministry chapters at Trinity International University, Moody Bible Institute, and Wheaton College, effectively launching what would become a brand new ministry hub to service the Midwest. In 2017, Mark became NSP’s second president. 

    Mark and his wife Shelley both grew up as missionary kids and now have three young children of their own,  Abigail, 7, Anna, 5, and Luke, 1. Together they live in Wheaton, IL, and attend College Church where Mark serves as chairman of the Evangelism Committee.

  • Kellee Popp

    Development DIRECTOR

    As a Biola freshman, Kellee was looking for an outlet to apply what she learned from her associates degree  in Biblical Studies at Calvary Chapel Bible College, when she heard the vision of the National School Project from Warren Willis. Convinced of the necessity of this ministry work, Kellee spent three years serving in student leadership before graduating with a B.S. in Christian Teaching in 2007 and joining staff full-time. 

    Since then, Kellee has served in multiple capacities in NSP as the first Training Director, the first California  State Director, and the first Development Director. In these roles, Kellee pioneered the creation of NSP’s Outreach Guide, a training resource that has become the foundation of NSP’s leadership development and mentorship model. Kellee also oversaw and developed HomeTown Trips, an initiative that paved the way for rapid ministry expansion and growth in new areas. 

    Kellee and her husband Mike live in Long Beach, CA, with their newborn daughter Eisley, and attend Arbor  Road Church where Mike serves as an elder.

  • Ben Flemming


    Ben has been working with NSP for over thirteen years. Starting with volunteer work as a Campus Mentor  at Sonora High School, Ben soon joined staff and became the Biola Chapter Director in 2008 after graduating with a B.A. in Humanities-Philosophy. Since then he has also served as NSP’s Director of

    Central Operations, but has definitely found his niche as the Human Resources Director.  

    Ben and his wife Laura have been married for seven years and are the proud parents of Samuel, their 1-year-old, and Davy, their adopted son who just turned 4. They are members at Redeemer Church in La Mirada, where Laura serves on the worship team and Ben serves as the Finance Director. In his work, he constantly recalls 1 Corinthians 15:58, “Therefore, my beloved brothers, be steadfast, immovable, always  abounding in the work of the Lord, knowing that in the Lord your labor is not in vain.”