Students from Deep Creek Middle School in Chesapeake, Virginia, present their STEM project to judges at the Samsung Solve for Tomorrow National Finalist Pitch Event on Monday in New York. The students created a website and app for high-need students with poor vision to access free prescription glasses. (Jon Simon)

Owensville High School students in Missouri saw the rise in school shootings as an opportunity to help kids across the country. They invented a secure door lock to prevent intruders from coming in.

The project is one of three that on Tuesday won Samsung’s Solve for Tomorrow Contest. Projects from schools in Virginia and North Carolina also won the national competition that challenges students to use STEM skills to solve real-world problems. Each school will be awarded $100,000 in Samsung technology and supplies.

At Deep Creek Middle School in Chesapeake, Virginia, students learned that school-age kids have undiagnosed vision problems. They created an app for schools to match students with donated eye glasses and free eye exams nearby. The kids are working to expand this service to other schools.

Students at Holly Grove Middle School in Holly Springs, North Carolina, wanted to find a way to stop cars from passing stopped school buses during pickups and drop-offs. So they created a school bus stop sign and sensor to alert drivers that a bus is approaching.

Holly Grove was also named this year’s Community Choice Winner for generating the most online votes. That award comes with an additional $10,000 in technology for the school.

The winners were selected from thousands of schools that submitted projects in October.

“This year’s national winners were truly impressive not only because of the passion and curiosity they have for solving critical community issues, but also because each school’s innovation represents a tangible solution capable of achieving measurable community impact,” said Ann Woo, senior director of corporate citizenship at Samsung.

The three national winners will be honored in May at a luncheon in Washington, where they will also show the projects to their state’s congressional representatives.