Your flight should begin at the First Flight Airport next to the Wright Brothers National Memorial (See http://binged.it/zVFqX3). The challenge is like a race, but the winner is not necessarily the quickest to the finish line, but the team with the best objective function results. Your objective function results will directly affect your technical merit score. The higher the objective function value (which you seek to maximize), the higher your score.
Your team score will be a composite of your design notebook score based on the National Scoring Rubric (35%), your presentation at the National 4-H Conference Center in Washington DC (30%), and technical merit / design viability (35%). The teams with the top three scores will present to a blue ribbon panel at the Smithsonian National Air and Space Museum who will determine the winner.
You may want to review refueling options that stop at airports in route to allow you to carry more useful payload to increase your objective function result. If you chose to make a refueling stop, the Mission Analysis Mathcad worksheet will assess 30 minutes to your time. This will impact your average velocity.
Feel free to email me if I can provide any additional clarification, or for help as an aeronautical engineering mentor.