Garrett Neese/Daily Mining Gazette Isha Mandal, 6, bowls at the Students for Sustainability booth during Saturday’s annual Western U.P. STEM Fair and Festival as group member Lauren Gray collects the pins. They used the festival to showcase their bottle brick project, in which used bottles are filled with pieces of film plastics and other nonrecyclables to create a strong, dense building material. The group hopes to build a bench with the materials and showcase it in Michigan Technological University’s library.

HOUGHTON — Students tested their hypotheses on everything from the best killer of bacteria to the fastest model of paper plane during Saturday’s annual Western U.P. STEM Fair and Festival, held at Michigan Technological University.

This year’s fair had 40 projects by 45 students from fourth through eighth grades. Students could come from throughout the five western U.P. counties.

“The energy in that room was really exciting with the students, and they’re so happy to share what they’ve done, which is awesome,” said organizer Emily Geiger.

Houghton Middle School sixth-grade students Neeki Abnenasir and Molly Skyles did their project on finding the angle at which total internal reflection occurs in water — the point at which a light ray bounces back to the original medium (water) instead of refracting when the beam hits air.

Through testing with a laser and a tank, they found that to occur at any angle up to 48.6 degrees. After that, “it doesn’t reflect internally anymore,” Skyles said.

Garrett Neese/Daily Mining Gazette Amelia Talaga, 5, of Duluth, Minnesota, tries to make a foil boat that will float in water during Saturday’s Western U.P. STEM Fair and Festival.

Skyles’ dad had suggested the basic idea, and they took it from there. Ebnenasir first worried the project was too simple, but working on the project raised her hopes.

“After I understood how it works, I thought it was pretty cool, how it can reflect,” she said. “I thought the patterns it makes are pretty cool.”

They said they’ll probably do the fair again next year.

“I didn’t really want to come, because I knew it’s not going to work, the judges aren’t going to like it, but then I came and I liked it here,” Ebnenasir said. “I thought it was fun.”

Students had their choice of traditional science projects, or for the first time, competing in Invention Convention. Put on by the Henry Ford Museum, the national program asks students to identify a problem — whether personal or global — and then invent something to solve it.

Garrett Neese/Daily Mining Gazette This year, the Western U.P. STEM Fair and Festival added the ability to compete in the national Invention Convention program. To help out his brother, Ayden Mackey of Baraga made a snowplow that can fit on a child’s bicycle.

“At this level, their prototype doesn’t need to be functioning,” Geiger said. “Their invention could even be a drawing at this point in ideation. But it’s really to get students into that engineering design process.”

Baraga fifth-grader Ayden Mackey came up with a snowplow that can attach to a bicycle. His little brother had wanted to help him shovel, but at that point, it was still too hard for him, Mackey said.

Mackey’s invention has a V-shaped wedge narrowing outward. After the first trial, he added edges at the base to catch and push the snow.

Even as a cardboard prototype, it works, Mackey said. He’d also consider making a metal one.

The biggest thing he’s gotten out of it?

“My brother really loves it,” he said.

At the science festival downstairs, children could try out exhibits made by local groups.

Amelia Talaga, 5, of Duluth, Minnesota, was making a foil boat to see if it would float in water. Her mother, Melanie Talaga, is a Tech graduate and chemist who’d brought the family back for a visit.

Looking at the trend of girls losing interest in science when they hit middle school, Melanie is trying to instill that excitement in her daughter early.

“I volunteer in the schools,” she said. “At least in Duluth, there’s just not a lot of time for teachers to be giving hands-on science. So I think it’s good to approach students like it’s fun. And just on a Saturday it’s a good way to spend the day, especially when it’s not super-nice outside.”

Traditionally held on a weeknight, the fair was moved to Saturday afternoon this year to encourage more participation from Gogebic and Ontonagon counties. They drew four entries from Gogebic County, which Geiger hopes to increase next year.

The plan is to keep the event on Saturdays in future years. Following this year’s fair, there will be recap meetings to go over what worked, what needs to be improved, and how to get more students involved, Geiger said.

“We are going to really talk to some parents and some teachers to try and gather feedback on how we can make this a bigger event,” she said.