Two Gwinnett County Public Schools teams of high-performing science students traveled to Washington D.C., over the weekend for a national competition.

They joined 58 other teams at the Science Olympiad National Tournament, held from Thursday through Saturday on the campus of George Washington University.

A team from Brookwood High School placed 25th in the national competition, and a team from Duluth High School placed 31st.

Students competed in several individual events. Some used their engineering skills to design robots that could pick up objects and airplanes with impressive flight times. Others performed experiments using skills in chemistry and physics.

"The kids worked extremely hard, and it really showed," said AP physics teacher Joe Cox, one of five coaches for the Brookwood High team.

Individual medals went to students on the teams who finished among top performers in their events.

Kyle Carnahan, 18, a graduating senior at Brookwood, received a fourth-place medal for creating a balsa wood plane that weighed less than a quarter and has been able to fly for about three minutes. Next fall, he will be studying aerospace science at Georgia Tech.

"We had a great team this year," said Carnahan. "The competition has been really fierce. It's been a really great experience."

Other individual medals were awarded to Duluth High teammates who won third place in the disease detective event and Brookwood High teammates who took fifth place in chemistry lab and sixth place in food science, Cox said.

To qualify for the tournament, Brookwood and Duluth high schools had to place in state competition. Brookwood won the state title for high schools. Duluth placed second.

Sangbeom Kim, a rising senior at Brookwood, said his team was thrilled with the opportunity to compete at the national level. Last year, the Brookwood team wasn't even among the top 10 in the state.

"We weren't expecting this," Kim said. "It's been amazing."