A&E Seven young adults posed as high school students for a semester on the A&E series "Undercover High." The undercover students discovered that smartphones have completely changed the lives of teenagers. Smartphones have become distractions in the classroom and have made problems like bullying and depression worse. High school isn't what it used to be. In fact, rapidly changing technology has made the typical American high school experience nearly unrecognizable for the average adult. No technological advance has changed the game more than smartphones, according to seven young adults who relived their high-school years on the A&E show "Undercover High." The show follows the adults aged 21 to 26 as they posed as students at Highland Park High School in Topeka, Kansas for the spring 2017 semester.