Director Joe Nussbaum (“Sydney White,” “Sleepover”) directs a debut script by Katie Wech for an uncommonly bland story of high school students getting ready for the prom. Oh darn, all the “Starry Night” decorations go up in flames! Only three weeks to go! The tweedy principal forces working-class, motorcycle-riding bad-boy-with-attitude Jesse (Thomas McDonell) to help Nova (Aimee Teegarden), the straight-A class president and head of the Prom Committee. He sneers that she is “winning the award for most awards.” She recalls: “You were the guy who cried when the hamster died in third grade.” As they fall for each other, various classmates pick their dates. Co-producer Justin Springer calls the spring rite of passage “a magnifier that allows teenage emotions to come out.” Although affectionate towards its well-scrubbed cast, the PG-rated “Prom” is no lens on adolescence. Acne and alcohol are absent at Brookside High School where kids take AP, not STD, tests. At Walt Disney Pictures’ press and promotional screening, ‘tweens in attendance seemed outnumbered by twentysomethings who loudly mocked afterschool cliches that hardly qualified as camp. With Danielle Campbell, Yin Chang, Kylie Bunbury, Nicholas Braun, Jared Kusnitz, Jonathan Keltz, De’Vaughn Nixon, Nolan Sotillo, Cameron Monaghan, Joe Adler, Janelle Ortiz, Raini Rodriguez. 104m. (Bill Stamets)