OAKLEY -- Necks craned to watch the rocket as it soared skyward.
"65! Who's was that?" said Freedom High School chemistry teacher Bridget Gengler as a student recorded the measurement on a clipboard.
About 2,100 math and science students spent four days this week launching rockets they'd made out of paper and tape from the Oakley campus's soccer field in an exercise designed to teach them how to think like scientists.
Teams of four took turns connecting their creations to an air compressor that shot them into the sky with up to 42 pounds of force per square inch.
The goal was to acquaint students with the practice of formulating and testing a hypothesis. Each team made two, the first serving as a control; they then tweaked a feature on the other and, after predicting how the rockets would fly, compared their performances.
Nicholas Lopez and his classmates used rectangular fins instead of triangular ones the second time around; 14-year-old Alexis Rodriguez attached four fins instead of three and sliced off the tips at an angle to reduce wind resistance.
To calculate how high each rocket ascended students had to envision a right triangle formed by the intersection of a rocket's vertical trajectory and an 100-foot line that extended across the field from the launch site.
Designated "trackers" then measured the angle formed where the end of that line met the triangle's hypotenuse.
To do that, students used inclinometers made from rectangular sheets of cardboard with pendulums fashioned from strings and plumblines. When they tilted the cardboard to squint through an attached scope at an airborne rocket, the dangling string would align with one of the lines drawn on the cardboard, each representing a different angle.
Once students knew the angle, they could use geometry or trigonometry to calculate the rocket's height.
Helping with the event were volunteers with the Patriots Jet Team Foundation, a nonprofit based at Byron Airport that offers activities to stimulate young people's interest in aerospace.
The foundation provided the prizes for the teams with the highest-reaching rockets, experiences that range from a behind-the-scenes look at an air show featuring the Patriot Jet Team to a free flight in a small plane and a nine-session ground school course.
But shooting off rockets goes beyond fun and games -- organizers hope that students will apply the process of critical thinking to other assignments.
"If you attach an emotion to their experience they're more likely to remember it," said biology teacher Cynthia Banducci. "They can remember, 'My rocket didn't do so well, why was that?' It gets them thinking in the scientific method."
Dave Harte agrees, noting that the hands-on activities students do in his engineering classes -- including building actual rockets that soar thousands of feet from scratch -- are the ones that make the biggest impression.
"I think students learn a lot more this way than reading about things in a book," he said.
Contact Rowena Coetsee at 925-779-7141. Follow her on Twitter.com/RowenaCoetsee