A middle school student emerged from the audience and was handed a microphone.

She was asked to sing a note above a Rubens tube, a metal pipe with holes poked through horizontally, and as she sang, flames leaped from the tube, becoming higher with each pitch.

The Rubens tube, presented by X-Labs, a student organization, was one of manyexhibits the 18,000 students from elementary, middle and high schools across the state could participate in at USFs 41st Engineering Expo on Friday and Saturday.

The event showcased science, technology, engineering and mathematics (STEM) programs. Student organizations and local businesses set up demonstrations and hands-on activities to teach students about STEM topics.

Inside the Engineering II building were booths from Tampa Electric, Legoland, Busch Gardens and Lockheed Martin.

The expo was a fundraiser for the engineering department, initially, Paulette Skowronek, a junior majoring in chemical engineering and director of marketing for the Expo, said. Now its grown into an educational opportunity to bring STEM to students.

X-Labs was among the most popular displays at the Expo, using fire demonstrations and a lightning show.

Science and technology can be fun and interesting, Coyt Barringer, X-Labs president and a freshman majoring in electrical engineering, said. You can do something really impressive and sit back to take in the results of your hard work. We want to inspire (students) to like this kind of stuff.

Barringer said X-Labs spent four months preparing for the Expo.

They demonstrated a fire tornado a wire net shaped in a tube which spun fire until it looked like a tornado.

Barringer explained to the audience that this dangerous phenomenon often occurs in forests during wildfires. Students screamed as the tornado flames grew over the top of the net.

Though it was too dangerous to perform inside, X-Labs played a YouTube video of themselves blowing up a microwave with thermite, a combination of aluminum powder and iron(III) oxides. As the aluminum powder is exposed to the iron, it creates a heated reaction and is three times hotter than liquid magma, Joe Register, a Ph.D. student, said.

X-Labs filmed the reaction of thermite inside a microwave. After a few seconds, the microwave caught on fire and the thermite burned a hole through the bottom of the machine. When the video was over, they brought out the microwave to show the students.

They also presented their 10-foot and 3-foot Tesla coils. Register said the 10-foot coil didnt work Thursday night but ran fine for the demonstrations. It took them two years to build the coil, which sparked musical notes to songs such as Secrets by One Republic and One by Swedish House Mafia.

In the future wed like to do more shows like this one every three to four months, Register said. For now were going to work on improving our
equipment.