When her mother had trouble seeing out of the passenger side of the family’s Jeep Grand Cherokee, Alaina Gassler thought: science-fair project! But the Chester County teenager tinkered for hours with a miniature camera and other gadgetry, and the car’s “blind spot” stubbornly remained. Fifty miles away, another young science whiz could relate. Seeking to thwart the invasive pests called spotted lanternflies, Rachel Bergey had wrapped maple trees in tinfoil on her family’s Montgomery County farm. Yet to her dismay, some of the insects simply crawled beneath the protective covering. The two girls are not frustrated anymore. They won national acclaim in October at the Broadcom MASTERS science competition for middle-school students, Gassler with the top $25,000 prize and Bergey claiming one of four $10,000 awards. Now in ninth grade, the two 14-year-olds first met in April when they entered their projects at the Delaware Valley Science Fair. On that occasion, the results were reversed — Bergey earning the gold medal and Gassler the silver. Bergey, a home-schooled student who lives in Harleysville, said she was happy to trade places with her electronics-minded counterpart. “She is aw...