Four guys quacking like a duck prompted Central Catholic High School senior Rick Szczublewski, who was blindfolded, to move forward.
Another sound they made - something like "mook, mook," - turned him in one direction. Imitating a techno beat turned him in the other.
This wasn't a game or some initiation ceremony for a school club. Even though the exercise was a component of a physics lab, it was a struggle at times for those watching this "science experiment" at the school yesterday to keep from laughing.
Physics teacher Michael Petro assigned his seniors the task of creating a guidance system for a blindfolded person using only a system of sounds. The blindfolded students had to navigate the course and drop tennis balls into four buckets.
Students couldn't use recognizable words in any language to guide their teammates.
While Mr. Szczublewski's team relied on voice noises and stomping their feet - which almost sounded like a primitive language - other teams used bells, drumsticks, sandpaper, a cell phone, and even a child's xylophone.
"I'm really excited they are all thinking creatively and critically," Mr. Petro said while one of the teams attempted the maze yesterday. "The fun for me comes because they are all participating together."
The senior class is studying sound and its properties, so the exercise is relative.
Nicole Moore got stumped midway through the course when she could not remember what the sound of sandpaper rubbing indicated.
"Oh, man, higher," she said after her time was up.
Not many teams were able to complete the entire course and drop a tennis ball into each four buckets within the allotted 7 1/2 minutes.
One team's attempt resembled a comedy routine, drawing muffled laughter from Mr. Petro and reporters who were invited to watch.
Blindfolded by a satin sleeping mask and armed with a lacrosse stick and five tennis balls, senior Kevin Jansen moved quickly as his team used a combination of voice sounds and other noises to direct him. But actually dropping the ball successfully into the buckets was the real challenge.
Mr. Petro said he designed the project based on a similar one he completed in high school.