First, students built rockets from two-liter soda bottles, cardboard or plastic fins, using water with pressure (60 psi) as the propellant. Trajectory, center of mass, and correct placement are all part of the rocket launch. After testing the rocket and making any needed adjustments, an official launch took place for the final competition.
The objective for each rocket is to have the longest "hang time" in the air from the time of launch. The winners were a team of 8th graders Zhaquan Calhoun (in the front) and Jahaan Holmes (in the back) with a "hang-time" of eleven seconds.
Watch their launch here: NMS Bottle Rocket Launch