MOSSVILLE — Tatum Pond and Ally Sigman, both students at Germantown Hills Middle School, spent Friday “nerding out,” as they called it, at the Caterpillar Inc. Technical Information Center.

Caterpillar’s “Introduce a Girl to STEM Day” was the kind of event where middle-school girls jumped at the chance to play games like “Wheel of Engineering,” the technical version of “Wheel of Fortune.”

While Pond and Sigman called it “nerding out,” organizers aspired to increase the number of girls interested in studying science, technology, engineering and math, better known as STEM.

“We’re really trying to target girls between fifth and eighth grades because that’s when we see a huge drop-off,” said Brooke Hart, a Caterpillar engineer who is part of Cat’s Women’s Initiative Network, which hosted the workshop.

The number of people graduating from college with STEM-related degrees is declining throughout the United States, Hart said, but especially among women. She said women account for only 20 percent of all bachelor of science degrees in engineering.

“Introduce a Girl to STEM Day," which began in 2013, is also part of Caterpillar’s effort to create a school-to-STEM pipeline of future female Caterpillar employees.

Almost 500 students from 45 schools throughout the area attended the event Thursday or Friday.

As far as Shiva Mittal was concerned, the girls didn’t necessarily have to have the highest grades in math and science to participate.

“I think the interest is more important at this point,” said Mittal, a computer scientist at Cat who works with Girls Who Code, a computer club for teen girls whose mission is to close the gender gap in technology. “The aptitude can come later, but there’s got to be the interest.”

Each participant attended four different hands-on activities, all designed to spark an interest in STEM, show how STEM relates to everyday life, and expose them to girls and women already involved in STEM fields.

Female members of Peoria Notre Dame High School’s FIRST Robotics team helped lead the workshop on robotics. Members of the Society of Women Engineers (SWE) guided them through the intricacies of transforming a piece of paper into a robotic inchworm. Librarians from the tech center taught them the relationship between engineering, making buttons or kazoo-like instruments, and why both are important to Caterpillar. The women involved with Girls Who Code introduced them to the similarities of creating a Lego project and computer coding.

Bell Watson and her classmates at Central Junior High School in East Peoria discovered that something as simple as the kazoo-like instrument — a “sound sandwich” made with Popsicle sticks, rubber bands and straws — held lessons in engineering.

“The tighter the rubber band, the higher the pitch,” Watson explained.

Laura Turner, a librarian at the tech center, told them the field of acoustical engineering is devoted to sounds and vibration. There are Caterpillar engineers, Turner said, who work primarily in acoustical engineering.

In the Lego project, a team had to arrange seven Legos, then write instructions clear enough for a different team to rebuild the Legos in the same arrangement. The project is a simple introduction to technical writing, computer coding, and the importance of being specific and accurate.

Sigman already knows she wants to be a biomedical engineer. Pond’s career interests are currently split between literature and biology. Their favorite workshop was the inchworm with the electronic building blocks, mainly because they won the inchworm race.

Both girls said the activity promoted problem-solving and teamwork.

“It might have been more interesting if they put us in teams with people we didn’t already know,” Pond said. “But that’s just my personal opinion because I like to test my limits.”

Pam Adams can be reached at 686-3245 or padams@pjstar.com. Follow her on Twitter @padamspam.